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Study Material and Notes of Ch 7 Conservation of Plants and Animals Class 8th Science

Deforestation

Deforestation is the process of clearing of forests in order to use the land for industrial, agricultural, and other purposes.

Causes of deforestation

Natural causes
Forest fire
Severe droughts
Man-made causes
Using land for agricultural purposes
Rapid urbanization
Procurement of wood for fuel and furniture

Consequences of deforestation

Increase in the level of carbon dioxide in atmosphere, which leads to global warming
Lowering of ground water levels
Increase in pollution level and temperature
Decrease in fertility of soil and amount of rainfall
Increase in frequency of droughts and floods
Desertification- conversion of fertile lands into deserts.

Biodiversity

Biodiversity is the species richness of the biosphere. It is defined as the number and variety of life forms such as plants, animals and microorganisms in an area.

It supports all the essential living resources such as wild life, fisheries and forests.

Forests help in maintaining the delicate balance of nature.

Animals living in forests are called wild animals.

The plants found in a particular area are known as flora of that area.

The animals found in a particular area constitute fauna of that area.

Those species of plants and animals, which are found only in a particular area, are called endemic species.

Species is a group of organisms in population which are capable of interbreeding.

The animals, whose numbers are diminishing to a level that they might face extinction, are called endangered animals.
For example: tiger, lion, and elephants

Project tiger was launched by the government of India to protect endangered tigers in their natural habitat.

The flora and fauna of a particular habitat can be protected through special protected areas.

Protected areas

Wildlife sanctuary

It is the place where wild animals are protected from hunting and are provided with suitable living conditions.
For example: Madhumalai wildlife sanctuary in Tamil Nadu, Chilika bird sanctuary in Orissa, etc.

National parks

These are the areas reserved for wildlife. They are maintained and preserved by the government for the public to visit.
For example: Ranthambore National Park in Rajasthan,

Kanha National Park in Madhya Pradesh, etc. Satpura National Park is the first reserve forest of India.

Biosphere Reserves

It is a large protected land for conservation of wild life, plant and animals resources, and the traditional life of the tribal groups living in the area.
For example: Pachmarhi Biosphere Reserve and Nilgiri Biosphere Reserve in India.

Red Data Book

It is the source book maintained by IUCN (International Union for Conservation of Nature and Natural resources). It keeps a track record of various endangered species of plants and animals.

Migration

It is the movement of birds and animals from their original habitat to other places at a particular time.

Migratory birds fly to distant areas every year during a particular time because of climatic changes- their original habitat becomes very cold and inhospitable lack of food availability

Numerous migratory birds including ducks, geese, flamingos, and cranes fly to India every year.

Recycling of paper

One ton of paper is made from about seventeen fully-grown trees.
Papers should be recycled and reused to conserve forest.
Each paper can be recycled three to seven times.
Recycling of paper saves trees, energy and water.
It prevents the release of harmful chemicals emitted during paper manufacturing in nature.

Reforestation

Restoring of destroyed forests by planting new trees is called reforestation.
It helps in checking environmental degradation.

पठन सामग्री, अतिरिक्त प्रश्न और उत्तर और सार - पाठ 18 - अक्क महादेवी (Akk Mahadevi) आरोह भाग - 1 NCERT Class 11th Hindi Notes

सारांश

कवयित्री अक्कमहादेवी द्वारा रचित वचन में प्रभु-भक्ति में स्वयं को समर्पित करने की बात की गई है| प्रथम कविता या वचन में इंद्रियों में नियंत्रण का संदेश दिया गया है| यह उपदेशात्मक न होकर प्रेम-भरा मनुहार है| दूसरा वचन एक भक्त का ईश्वर के प्रति पूर्ण समर्पण है| कवियित्री ऐसी निस्पृह स्थिति की कामना करती है जिससे उनका स्व या अहंकार पूरी तरह से नष्ट हो जाए|

1. हे भूख! मत मचल.........................संदेश लेकर चन्नमल्लिकार्जुन का

कवयित्री अक्कमहादेवी भगवान शिव की परमभक्त थीं| प्रस्तुत पद में उन्होंने सांसारिकता त्यागकर शिव की आराधना में लीन होने का संदेश दिया है| वे कहती हैं कि सांसारिक वस्तुओं की चाह में और अधिक पाने की लालसा नहीं होनी चाहिए| भूख, प्यास, नींद, क्रोध, मोह, ईर्ष्या, लोभ आदि मन के ऐसे विकार हैं जो प्रभु-भक्ति के मार्ग की बाधाएँ हैं| इन विकारों का त्याग करके ही हम प्रभु-भक्ति में लीन हो सकते हैं| कवयित्री चन्नमल्लिकार्जुन अर्थात् भगवान शिव का भक्ति-संदेश लेकर आई हैं| वे चाहती हैं कि सांसारिकता का त्याग करके हम स्वयं को प्रभु के चरणों में समर्पित कर दें|

2. हे मेरे जूही के फूल.....................झपटकर छीन न ले मुझसे

प्रस्तुत वचन में कवयित्री ने ईश्वर को जूही के फूल की उपमा दी है| उनके प्रभु जूही के फूल की तरह कोमल, मनोरम और सुंदर हैं| वे ईश्वर से कामना करते हुए कहती हैं कि ऐसी स्थिति उत्पन्न कर दें कि उन्हें भूख मिटाने के लिए भीख माँगना पड़े| यहाँ तक कि भीख मांगने पर भी उन्हें कोई भीख न दे| भीख मिलने पर कोई कुत्ता उसे छीन ले और कवियित्री की झोली खाली रह जाए| वह अपने घर-गृहस्थी अर्थात् मायावी संसार को भूलने की बात करती हैं ताकि सभी प्रकार के सांसारिक कष्ट दूर हो जाए| इस प्रकार वह चाहती हैं कि इससे उनका अहंकार नष्ट हो जाए और वह प्रभु के चरणों में समर्पित हो जाए|

कवयित्री-परिचय

अक्क महादेवी

जन्म - 12 वीं सदी, कर्नाटक के उडुतरी गाँव, जिला- शिवमोगा में|

प्रमुख रचनाएँ- हिंदी में वचन सौरभ नाम से, अंग्रेजी में स्पीकिंग ऑफ़ शिवा के नाम से|

इतिहास में वीर शैव आन्दोलन से जुड़े कवियों, रचनाकारों की एक लंबी सूची है| अक्कमहादेवी भी इस आंदोलन से जुड़ी एक महत्वपूर्ण कवियित्री थीं| कन्नड़ भाषा में अक्क शब्द का अर्थ बहिन होता है| अक्कमहादेवी ने पुरूष वर्चस्व समाज के विरूद्ध आक्रोश की अभिव्यक्ति के रूप में अपने वस्त्रों को भी उतार फेंका|

अक्क के कारण शैव आंदोलन से बड़ी संख्या में स्त्रियाँ जुड़ीं और अपने संघर्ष और यातना को कविता के रूप में अभिव्यक्ति दी| इस प्रकार अक्कमहादेवी की कविता पूरे भारतीय साहित्य में इस क्रांतिकारी चेतना का पहला सर्जनात्मक दस्तावेज है और संपूर्ण स्त्रीवादी आंदोलन के लिए एक अजस्र प्रेरणास्रोत भी|

कठिन शब्दों के अर्थ

• पाश - जकड

• ढील - ढीला करना

• मद - नशा

• चराचर - जय और चेतन

• चन्नमल्लिकार्जुन - शिव

NCERT Solutions of पाठ 18 - अक्क महादेवी

पठन सामग्री, अतिरिक्त प्रश्न और उत्तर और सार - पाठ 19 - सबसे खतरनाक (Akk Mahadevi) आरोह भाग - 1 NCERT Class 11th Hindi Notes

सारांश

प्रस्तुत कविता ‘सबसे खतरनाक’ दिनोंदिन अधिकाधिक नृशंस और क्रूर होती जा रही दुनिया की विद्रूपताओं के चित्रण के साथ उस खौफनाक स्थिति की ओर इशारा करती है, जहाँ प्रतिकूलताओं से जूझने के संकल्प क्षीण पड़ते जा रहे हैं| जड़ स्थितियों को बदलने की प्यास से मर जाने और बेहतर भविष्य के सपनों के गुम हो जाने को कवि ने सबसे अधिक खतरनाक स्थिति माना है|

कवि के अनुसार मेहनत का लुट जाना, पुलिस के अत्याचारों का शिकार होना, लोभ या धोखे की प्रवृत्ति से ग्रस्त होना इतना भी खतरनाक नहीं होता| अन्याय को चुपचाप सहना, अपने चारों ओर छल-कपट देखकर भी शांत रहना भी खतरनाक नहीं है| सही होते हुए भी गलत को बर्दाश्त करना तथा अल्पज्ञानी से ज्ञान प्राप्त करना भी उतना खतरनाक नहीं है जितना कि निष्क्रिय होकर जीवन व्यतीत करना है| केवल अपने काम तक सिमट कर रह जाना बहुत बुरी बात है| लक्ष्यहीन होकर जिंदगी बिताना भी खतरनाक है| कवि के अनुसार परिवर्तनशील संसार में जड़ होकर रहना भी खतरनाक है| समय के साथ गतिशीलता ही जीवन को सार्थक बनाता है| हमारी नजर ऐसी होनी चाहिए जिसमें सबके लिए परें व्याप्त हो| अंधविश्वास और रूढ़ियों वाली सोच सबसे खतरनाक होती है| ऐसी आस्था जो अन्याय के विरूद्ध आवाज उठाने के बजाय शांत रहने की प्रेरणा दे, वह बुरी होती है| वह गीत भी खतरनाक होता है जो व्यक्ति के मन में शोक के भाव उत्पन्न करे या निराशा से भर दे| आत्मा की आवाज को अनसुना करने वाली सोच भी खतरनाक होती है| इस प्रकार कवि ने समाज में व्याप्त अनेक बुराइयों को उजागर करते हुए कहा है कि हमें समय के अनुसार प्रगतिशील रहना चाहिए| हमें रूढ़िवादी विचारधारा को त्याग कर बौद्धिक और आत्मिक रूप से जाग्रत होना चाहिए|

कवि-परिचय

पाश (अवतार सिंह संधू)

जन्म- सन् 1950, तलवंडी सलेम गाँव, जिला जालंधर (पंजाब) में|

प्रमुख रचनाएँ- लौह कथा, उड़दें बाजां मगर, साडै समिया बिच, लड़ेंगे साथी (पंजाबी); बीच का रास्ता नहीं होता, लहू है कि तब भी गाता है (हिंदी अनुवाद)|

मृत्यु: सन् 1988 में|

पाश समकालीन पंजाबी साहित्य के महत्वपूर्ण कवि माने जाते हैं| मध्यवर्गीय किसान परिवार में जन्मे पाश की शिक्षा अनियमित ढंग से स्नातक तक हुई| पाश की कविताएँ विचार और भाव के सुंदर संयोजन से बनी गहरी राजनीतिक कविताएँ हैं जिनमें लोक संस्कृति और परंपरा का गहरा बोध मिलता है| उनकी कविताओं में वह व्यथा, निराशा और गुस्सा नजर आता है जो गहरी संपृक्तता के बगैर संभव ही नहीं है|

कठिन शब्दों के अर्थ:

• गद्दारी- व्यक्ति, देश या शासन से द्रोह या धोखा
• बैठे-बिठाए- अनायास या अकारण
• तड़प- बेचैनी
• वीरान- उजड़ा हुआ
• मरसिया- करूण रस की कविता जो किसी व्यक्ति की मृत्यु पर लिखी जाती है
• रूह- आत्मा
• चौगाठों- चौखटों

NCERT Solutions of पाठ 19 - सबसे खतरनाक

Study Material and Notes of Ch 8 Cell - Structure and Functions Class 8th Science

Introduction

• Cell
→ Discovery of cell
• Cell Theory
• Types of Organisms on the basis of cell
→ Unicellular organisms
→ Multicellular organisms
• Shape of the cells
• Size of the cells
• Cell Structure and functions
• Types of Cells
→ Prokaryotic cells
→ Eukaryotic cells
• Components of the cell
→ Cell membrane
→ Cell wall
→ Cytoplasm
→ Nucleus
→ Chromosomes
→ Vacuoles
→ Plastids
→ Endoplasmic Reticulum
→ Golgi Apparatus
→ Lysosomes
→ Mitochondria
• Differences between plany and animal cells
• Diagram of Plant Cells and Animals Cells

Cell

Discovery of the Cell

→ Cells are the basic structural units and the building blocks of all living organisms.

→ Cell was discovered by Robert Hooke in 1665 after observing a piece of cork under a magnifying device.

→ Robert Hooke coined the term “cell”.

Cell Theory

→ Schleiden and Schwann proposed the cell theory.

→ According to cell theory: Cells are the basic structural and functional units of life.

→ All living organisms are made up of one or more cells.

→ New cells arise from pre-existing cells.

Types of Organisms on the basis of cell

(i) Unicellular Organisms
(ii) Multicellular Organisms

Unicellular organisms

• Number of Cells Organisms made of only a single cell are called unicellular organisms.
For example: Amoeba and Paramecium

→ All the basic functions such as digestion, respiration, excretion, etc. in these organisms performed by a single cell.

Multicellular organisms

• Organisms made up of more than one cells are called multicellular organisms.
For example: Humans, cow, rose, etc.

→ In these organisms, the cells show division of labour as particular set of cells are involved in performing a specific body function.

Shape of the Cells

→ Most of the cells have a definite shape.

→ Some cells such as that in Amoeba have no definite shape.

→ The human red blood cell (RBC) is spherical-shaped.

→ The muscle cells in humans are spindle-shaped.

→ The human nerve cells have elongated branched structure.

→ In plants and bacteria, the cell is enclosed in a protective covering called cell wall, which gives shape and rigidity to the cells.

Size of the Cells

→ The smallest cell is 0.1 to 0.5 micrometre in bacteria.

→ The largest cell is of size 170 mm x 130 mm, which is the egg of an ostrich.

→ Size of a cell has no relation with the size of an organism.

Cell Structure and Functions

→ In multicellular organisms, each organ system is made up of several organs.

→ Organs are further made up of tissues.

→ Tissues are groups of similar cells performing a specific function.

→ Number of cells Organisms made up of only a single cell are called unicellular organisms.
For example: Amoeba and Paramecium

→ Single cell in unicellular organisms performs all the basic functions such as digestion, respiration, and excretion.

→ Organisms made up of more than one cells are called multicellular organisms.
For example: Humans, cow, etc.

→ In multicellular organisms, the cells show division of labour as a particular set of cells are involved in performing a specific body function.

Types of cell

There are two types of cells.

(i) Prokaryotic cells
(ii) Eukaryotic cells

• Prokaryotic cells

Cells which do not have a well defined nuclear membrane and the nuclear material lies freely in the cytoplasm of the cell.
For example: bacteria, blue green algae.

• Eukaryotic cells

Cells having nucleus with well defined nuclear membrane.
For example: plant and animal cells

Components of the cell

Cell membrane

→ It is the protective layer that surrounds the cell.

→ Cell membrane selectively allows the entry of only some substances and prevents the movement of other materials.

→ Hence, it checks the transport of substances in and out of the cell.

Cell wall

→ In plants, an extra protective covering of a polysaccharide, cellulose is present.

→ It is called cell wall that protects plant cells from environmental variations.

Cytoplasm

→ It is a jelly-like substance present between cell membrane and nucleus.

→ It contains various cell organelles such as mitochondria, Golgi bodies, lysosomes etc.

Nucleus

→ It is a dense spherical body located at the centre of the cell.

→ It is surrounded by porous nuclear membrane.

→ It contains spherical body called nucleolus.

→ It also contains thread-like structures called chromosomes.

Chromosomes

→ These are the structures that carry genes and play an important role in inheritance.

→ Genes are the structural and functional unit of inheritance.

→ The entire living substance in a cell is known as protoplast.

Vacuoles

→ Vacuoles are fluid-filled membrane-bound structures in the cell.

→ In plant cells, a single large vacuole is present.

→ In animal cells, numerous small vacuoles are present.

→ The membrane of the vacuole is called tonoplast.

→ This membrane encloses a fluid called cell sap.

Plastids

→ They are present only in plant cells.

→ Plastids that contain green colour pigment chlorophyll are known as chloroplasts.

→ It is the chlorophyll that gives green colour to the leaves.

→ Chloroplast traps solar energy and utilizes this energy to manufacture food for the plant.

• Plastids are of two types:
(i) Leucoplasts
(ii) Chromoplasts

→ Leucoplasts are colourless and are used to store food while chromoplasts are plastids containing pigments.

→ Chloroplasts are a type of chromoplasts.

• Chloroplasts consist of two regions:
(i) grana (stacks of sac like membrane bound structures that contain pigment chlorophyll)
(ii) stroma (ground substance containing enzymes and starch grains)

Endoplasmic Reticulum (ER)

(i) Rough Endoplasmic Reticulum (RER): It is important for the synthesis and packaging of proteins.

(ii) Smooth Endoplasmic Reticulum (SER): It acts as storage organelle. It also helps in lipid (fat) synthesis.

Golgi Apparatus

→ It is made up of parallel arranged membrane-bound vesicles called cisternae.

→ It helps in storage, modification, and packaging of products in vesicles.

→ It helps in formation of glycoproteins and glycolipids.

Lysosomes

→ It is a membrane-bound structure that holds variety of enzymes.

→ Rich in all types of hydrolytic enzymes, which are active at acidic pH.

→ It is involved in the digestion of carbohydrates, proteins, lipids, and nucleic acids.

Mitochondria

→ It is a double membrane-bound structure.

→ The inner membrane of mitochondria is deeply folded to form cristae.

→ Cristae increase the surface area in the organelle.

→ It is the site of cellular respiration and hence known as ‘power house of cell’.

→ They have their own circular DNA.

→ They divide by fission.

Differences between plant and animal cells

Plant Cells	Animal Cells
Cell wall is present.	Cell wall is absent.
Nucleus is located in the periphery of the cell.	Nucleus is located in the centre of the cell.
Plastids are present.	Plastids are absent.
A large single vacuole is present in the centre of the cytoplasm.	Numerous small vacuoles are present in the cytoplasm.

Diagram of Plant Cells and Animal Cells

Study Material of A Letter to God (Summary, Character Sketches and Word Meanings) First Flight Class 10

Summary of the Chapter

Lencho was a farmer. He had the field of ripe corn dotted with the flowers. He hoped for a downpour or at least a shower. He was happy to see huge mountains of clouds. But suddenly strong wind began to blow with the large hailstones. The hail rained for an hour and the field was white as if covered with salt. The corn was totally destroyed. The hail has left nothing. He did not understand what to do. o But He had a great faith on god. He decided to seek help from god. He wrote a letter to god demanding 100 pesos. When the postman read the letter addressing to god he could not stop himself by laughing. But the post master who was a fat, amiable man decided to help Lencho. He collected 70 pesos from his friends, charity and he himself gave part of his salary. The following Sunday Lencho came to collect the money. But he was disappointed to find only 70 pesos. He was angry and he wrote again a letter to god demanding rest of the money. He also wrote that the god should not send the money through the post office because what he believed that the post office employees are bunch of crooks.

Quick Revision Notes

• Lencho’s crops had failed that year and he had only a single hope i.e. God!

• He wrote a letter to God “God, my crops have failed and my family is going to starve. I need some money- hundred pesos.”

• At the post office, the postmen saw such a queer letter and brought it to the postmaster.

• The postmaster was a man of sympathy and understand a man like Lencho.

• Postmaster observed that faith of Lencho was strong as a child’s so he decided to send an amount of hundred pesos to the poor farmer.

• Hundred pesos was a huge amount, the postmaster was able to collect only seventy pesos. However, he sent the money to Lencho.

• Lencho received the money with a belief that God had helped him.

• Lencho was sad and angry after counting the money as he received only seventy instead of hundred.

• Lencho wrote another letter to God and dropped the letter in the same postbox and went.

• The postmaster felt the biggest shock and shame in his life after opening Lencho’s second letter to God.

• Lencho had written, “God, of the money that I had asked for, only seventy pesos reached me. Send me the rest, since I need it very much. But don’t send it to me through the post because the post office employees are a bunch of thieves. Lencho.”

Word Meanings

Crest : top/the highest part of a hill
Dotted with : scattered over an area
Predict : foretell the future
Drape : cover
Locusts : insects which fly in big groups and destroy crops.
Solitary : lonely / single
Upset : disturbed
Conscience : an inner sense of right and wrong
Peso : currency of several Latin American countries
Amiable : friendly and pleasant
Correspondence : an act of writing letters
Resolution : a firm decision
Contentment : satisfaction
Crooks : dishonest persons / people

NCERT Solutions for Class 12th: Ch 6 Secondary Activities Fundamentals of Human Geography

Exercises

Page No: 53

1. Choose the right answer from the four alternatives given below.

(i) Which one of the following statements is wrong?
(a) Cheap water transport has facilitated the jute mill industry along the Hugli.
(b) Sugar, cotton textiles and vegetable oils are footloose industries.
(c) The development of hydro-electricity and petroleum reduced, to a great extent, the importance of coal energy as a locational factor for industry.
(d) Port towns in India have attracted industries.
► (b) Sugar, cotton textiles and vegetable oils are footloose industries.

(ii) In which one of the following types of economy are the factors of production owned individually?
(a) Capitalist
(b) Mixed
(c) Socialist
(d) None
► (a) Capitalist

(iii) Which one of the following types of industries produces raw materials for other industries?
(a) Cottage Industries
(b) Small-scale Industries
(c) Basic Industries
(d) Footloose Industries
► (c) Basic Industries

Page No: 54

(iv) Which one of the following pairs is correctly matched ?
(a) Automobile industry … Los Angeles
(b) Shipbuilding industry … Lusaka

(c) Aircraft industry … Florence
(d) Iron and Steel industry … Pittsburgh
► (d) Iron and Steel industry … Pittsburgh

2. Write a short note on the following in about 30 words.
(i) High-Tech industry
(ii) Manufacturing
(iii) Footloose industries

Answer

(i) High technology is the latest generation of manufacturing activities which is best understood as the application of intensive research and development (R and D) efforts leading to the manufacture of products of an advanced scientific and engineering character. Highly skilled specialists greatly

outnumber the actual production (blue collar) workers. Examples are robotics on the assembly line,

computer -aided design (CAD) and manufacturing.

(ii) Manufacturing literally means ‘to make by hand’. However, now it includes goods ‘made by machines'. It is a process which involves transforming raw materials into finished goods of higher value for sale in local or distant markets.

(iii) Footloose industries are not dependent on any specific raw material, weight losing or otherwise. They largely depend on component parts which can be obtained anywhere. They produce in small quantity and also employ a small labour force. It can be located in a wide variety of places.

3. Answer the following in not more than 150 words.

(i) Differentiate between primary and secondary activities.

Answer

Primary activities	Secondary activities
Primary activities involve extraction of raw materials from the earth's surface.	Secondary activities involve transforming of raw materials into finished goods.
Primary activities include hunting and gathering, pastoralism, fishing, forestry, mining and agriculture.	Secondary activities include manufacturing of various products like textiles, iron and steel, fertilizers, cement, etc.
They are almost the only source of food supply and raw materials for industries.	Secondary activities have their impact on health, education, transport and trade.
People engaged in primary activities are called red-collar workers.	People engaged in secondary activities are called blue-collar workers.

(ii) Discuss the major trends of modern industrial activities especially in the developed countries of the world.

Answer

Modern industrial activities involve the application of power, mass production of identical products
and specialised labour in factory settings for the production of standardised commodities.

Some major trends of modern industrial activities especially in the developed countries are:

• Specialisation of Skills of Production: Mass production involves production of large quantities of standardised parts by each worker performing only one task repeatedly.

• Mechanisation: Mechanisation refers to using gadgets which accomplish tasks. Automation is the advanced stage of mechanisation. Automatic factories with feedback and closedloop computer control systems where machines are developed to ‘think’, have sprung up all over the world.

• Technological Innovation: Technological innovations through research and development strategy are an important aspect of modern manufacturing for quality control, eliminating waste and inefficiency, and combating pollution.

Modern manufacturing is characterised by:
(i) a complex machine technology
(ii) extreme specialisation and division of labour for producing more goods with less effort, and low costs
(iii) vast capital
(iv) large organisations
(v) executive bureaucracy.

(iii) Explain why high-tech industries in many countries are being attracted to the peripheral areas of major metropolitan centres.

Answer

High-tech industries are the latest generation of manufacturing activities. It is the application of intensive research and development (R and D) efforts leading to the manufacture of products of an advanced scientific and engineering character. Professional (white collar) workers make up a large share of the total workforce. High qualified need better facilities such as institutions, hospitals, shopping malls, restaurants etc.

Neatly spaced, low, modern, dispersed, office-plant-lab buildings rather than massive assembly structures, factories and storage areas mark the high-tech industrial landscape. Planned business parks for high-tech start-ups have become part of regional and local development schemes.

Therefore, high-tech industries in many countries are being attracted to the peripheral areas of major metropolitan centres.

(iv) Africa has immense natural resources and yet it is industrially the most backward continent. Comment.

Answer

The continent of Africa is very rich in natural resources such as crude oil, copper, coal, manganese but they are still backward because:

• Colonial Exploitation: African countries remained under foreign rules who exploited the natural resources for their own benefits rather than developing industries and infrastructure.

• Lack of Human Resources: The continent lack good institutions and thus the people are not well educated and skilled. The utilization of natural resources demands human resources.

• Civil Wars: The civil wars in the countries of Africa are frequent. There is mass scale corruption in the governments of the African countries which hinder the growth of countries.

• Lack of technological development: The countries of Africa are technologically very poor. The exploration and extraction of natural resources could not be possible without technology.

Go to Index of Class 12th Fundamentals of Human Geography NCERT Solutions

Study Material of Long Walk to Freedom (Summary, Character Sketches and Word Meanings) First Flight Class 10

Summary of the Chapter

Nelson Mandela was born on July 18, 1918. He was the first South African President to be elected in a fully representative democratic election.

In life, every man has twin obligations: obligations to his family, to his parents, to his wife and children; and he has an obligation to his people, his community and his country. In a civil and humane society, each man is able to fulfill those obligations according to his own inclinations and abilities. But in a country like South Africa, it was almost impossible for a man of my birth and colour to fulfill both of those obligations.

In South Africa, a man of colour who attempted to live as a human being was punished and isolated. In South Africa, a man who tried to fulfil his duty to his people was inevitably ripped from his family and his home and was forced to live a life apart, a twilight existence of secrecy and rebellion.

He said as quoted, "I did not in the beginning choose to place my people above my family, but in attempting to serve my people, I found that I was prevented from fulfilling my obligations as a son, a brother, a father and a husband."
"I was not born with a hunger to be free. I was born free — free in every way that I could know. Free to run in the fields near my mother’s hut, free to swim in the clear stream that ran through my village, free to roast mealies under the stars and ride the broad backs of slow-moving bulls. As long as I obeyed my father and abided by the customs of my tribe, I was not troubled by the laws of man or God."

"It was only when I began to learn that my boyhood freedom was an illusion, when I discovered as a young man that my freedom had already been taken from me, that I began to hunger for it. At first, as a student, I wanted freedom only for myself, the transitory freedoms of being able to stay out at night, read what I pleased and go where I chose."

"Later, as a young man in Johannesburg, I yearned for the basic and honourable freedoms of achieving my potential, of earning my keep, of marrying and having a family — the freedom not to be obstructed in a lawful life. But then I slowly saw that not only was I not free, but my brothers and sisters were not free. I saw that it was not just my freedom that was curtailed, but the freedom of everyone who looked like I did. That is when I joined the African National Congress, and that is when the hunger for my own freedom became the greater hunger for the freedom of my people."

"It was this desire for the freedom of my people to live their lives with dignity and self- respect that animated my life, that transformed a frightened young man into a bold one, that drove a law-abiding attorney to become a criminal, that turned a family-loving husband into a man without a home, that forced a life-loving man to live like a monk."

"I am no more virtuous or self sacrificing than the next man, but I found that I could not even enjoy the poor and limited freedoms I was allowed when I knew my people were not free. Freedom is indivisible; the chains on anyone of my people were the chains on all of them, the chains on all of my people were the chains on me. I knew that the oppressor must be liberated just as surely as the oppressed."

"A man who takes away another man’s freedom is a prisoner of hatred; he is locked behind the bars of prejudice and narrow-mindedness. I am not truly free if I am taking away someone else’s freedom, just as surely as I am not free when my freedom is taken from me. The oppressed and the oppressor alike are robbed of their humanity."

Quick Revision Notes

• Nelsom Mandela swears in as the first black president of South Africa on 10th May 1994.

• At the time of his swearing two national anthems were sung. He wished that freedom in Africa should reign.

• The swearing in ceremony took place in the lovely sandstone amphitheater in Pretoria

• He addressed the rainbow gathering with a zest telling that never, never, and never again should it be that that beautiful land would experience the oppression of one by another.

• He wished that freedom in Africa should reign.

• The army officials who could have caught have and put him in jail before were saluting him to pay respect to the newly born democracy.

• The two national anthems were sung at the time of his swearing in ceremony.

• He recalls back the history and pays homage to the national martyrs who sacrificed their lives for the sake of their motherland.

• He tells about the martyrs were the man of extraordinary courage and wisdom and generosity.

• That’s why he pays homage to the national martyrs who sacrifice their lives for the sake of their motherland.

• The country of South Africa is rich in minerals and gems but the greatest wealth of country is its people.

• He tells no one is born hating another person because of the colour of his skin, or his background , or his religion.

• If people learn to hate, they can be taught to love too.

• He talks that man's goodness is a flame that can be hidden but never exhausted.

• He talks about the twin obligations-obligation towards his family & obligation towards his nation.

• While discharging his duties he found he was not free. Hence, he joined African National Congress fought for the freedom of his country.

• He well known about the oppressor must be liberated just as surely as the oppressed.

• The oppressor and oppressed are alike are robbed of their humanity.

NCERT Solutions for Class 12th: Ch 7 Tertiary and Quaternary Activities Fundamentals of Human Geography

Exercises

Page No: 63

1. Choose the right answer from the four alternatives given below.

(i) Which one of the following is a tertiary activity?
(a) Farming
(b) Trading
(c) Weaving
(d) Hunting
► (b) Trading

(ii) Which one of the following activities is NOT a secondary sector activity?
(a) Iron Smelting
(b) Catching fish
(c) Making garments
(d) Basket Weaving
► (b) Catching fish

(iii) Which one of the following sectors provides most of the employment in Delhi, Mumbai, Chennai and Kolkata.
(a) Primary
(b) Quaternary
(c) Secondary
(d) Service
► (d) Service

(iv) Jobs that involve high degrees and level of innovations are known as:
(a) Secondary activities
(b) Quaternary activities
(c) Quinary activities
(d) Primary activities
► (d) Primary activities

(v) Which one of the following activities is related to quaternary sector?
(a) Manufacturing computers
(b) Paper and Raw pulp production
(c) University teaching
(d) Printing books
► (c) University teaching

Page No: 64

(vi) Which one out of the following statements is not true?

(a) Outsourcing reduces costs and increases efficiency.

(b) At times engineering and manufacturing jobs can also be outsourced.

(d) There may be dissatisfaction among job seekers in the countries that outsource the job.
► (c) BPOs have better business opportunities as compared to KPOs.

2. Answer the following questions in about 30 words.

(i) Explain retail trading service.

Answer

Retail trading service is the business activity concerned with the sale of goods directly to the consumers. Most of the retail trading takes place in fixed establishments or stores solely devoted to

selling.

(ii) Describe quaternary services.

Answer

Quaternary services involve the collection, production and dissemination of information or even the

production of information. These activities centre around research, development and may be seen as an advanced form of services involving specialised knowledge and technical skills.

(iii) Name the fast emerging countries of medical tourism in the world.

Answer

India, Thailand, Singapore and Malaysia are the fast emerging countries of medical tourism in the world.

(iv) What is digital divide?

Answer

Opportunities emerging from the Information and Communication Technology based development is unevenly distributed across the globe. There are wide ranging economic, political and social differences among countries. While developed countries in general have surged forward, the developing countries have lagged behind and this is known as the digital divide.

3. Answer the following questions in not more than 150 words.

(i) Discuss the significance and growth of the service sector in modern economic development.

Answer

Services are usually defined as ‘activities’ which are relatively detached from material production and hence are not directly involved in the processing of physical materials.

• Services are an important part of modern economic development which include health, education, law, governance and recreation etc.

• Services are provided to individual consumers who can afford to pay for them. Many services have now been regulated with the growth of population. Making and maintaining highways and bridges, maintaining fire fighting departments and supplying or supervising education and customer -care are among the important services most often supervised or performed by governments or companies.

• State and union legislation have established corporations to supervise and control the marketing of such services as transport, telecommunication, energy and water supply.

• Professional services are primarily health care, engineering, law and management. The location of recreational and entertainment services depends on the market.

• Today most people are service workers. Services are provided in all societies. But in more developed countries a higher percentage of workers is employed in providing services as compared to less developed countries.

• The trend in employment in this sector has been increasing while it has remained unchanged or decreasing in the primary and secondary activities.

(ii) Explain in detail the significance of transport and communication services.

Answer

The significance of transport and communication services:

• Transport and communication services are called lifeline of an economy.

• Transport is a service or facility by which people, materials and manufactured goods are physically carried from one location to another. Modern society requires speedy and efficient transport systems to assist in the production, distribution and consumption of goods. At every stage in this complex system, the value of the material is significantly enhanced by transportation.

• Communication services involve the transmission of words and messages, facts and ideas. The invention of writing preserved messages and helped to make communication dependent on means of transport. These were actually carried by hand, animals, boat, road, rail and air. Where the transport network is efficient, communications are easily disseminated. Certain developments, such as mobile telephony and satellites, have made communications independent of transport.

Go to Index of Class 12th Fundamentals of Human Geography NCERT Solutions

Study Material of Two Stories about Flying- His First Flight (Summary, Character Sketches and Word Meanings) First Flight Class 10

Summary of the Chapter

This story of a young seagull and He wouldn’t dare to fly, and the entire family member encourage him to fly but all went in vain, and for the same, he was harshly punished by his parents. He was left all alone on the ledge starving for 24 hours. He cried with hunger. After all his mother took final decision to put before him bait. It worked, he dived for a scrap of fish.

Mother was high up in the sky and he was in the open air falling down and down. Bravery is the fear is the victory. And he opened his wings and found himself flying. In this way to young seagull take his first flight. Hence, we can say parental encouragement and discipline play a extraordinary role in shaping the destiny of the young children.

Quick Revision Notes

• This story is about a young seagull, who was afraid of flying.

• Young seagull was full of pessimism.

• His parents and family members used to encourage him for his first flight but he doesn’t have enough courage to fly.

• He was left alone by his family members for 24 hours and he ate nothing.

• He was very hungry and he begged for food for mother.

• Young seagull’s mother diverted his mind from fear to food.

• He dived when he saw the food. He cried and screamed but his wings opened automatically and flapped his wings.

• After all he was joined by his family in his first flight.

Study Material of Two Stories about Flying- Black Aeroplane (Summary, Quick Revision Notes and Word Meanings) First Flight Class 10

Summary of the Chapter

The story revolves around the mystery, ‘who was another pilot?’

The story teller was on his flight go to England hoping to have a good English breakfast with his family. But during flight he saw great storm clouds ahead of him and clouds are looks like mountains. He risked entering in the clouds and everything turned black.

He saw another aeroplane without lights on its wings. The pilot waved his hand to the story teller and asked him to follow him. The story teller followed that another pilot as his compass, radio went dead. Even there was not enough fuel in his tank. With the help of another pilot, he landed safely and when he went to receptionist to thank the pilot he was informed by the lady that there was no any other plane flying in the sky that night.

Quick Revision Notes

• At the midnight a pilot of old Dakota aeroplane flies over Paris (France) towards England.

• Pilot was flies with the dreams of having breakfast in the morning and spending holidays with his family.

• Unfortunately he passes through huge black clouds.

• The compass, radio, fuel gauge and all other equipment turned dead. Even not enough fuel in fuel tank.

• Suddenly he noticed another pilot in black aeroplane waved his hand to follow his instructions.

• Suddenly he noticed a row of light on the ground and that’s runway, he lands safely.

• He went to receptionist and asks about the aeroplane. But he is dumbstruck to know that there is no aeroplane noticed on the radar that night.

• Many questions in his mind remain unsolved about the mysterious the black aeroplane.

NCERT Solutions for Class 11th: पाठ 20 - आओ, मिलकर बचाएँ आरोह भाग-1 हिंदी (Aao milkar bachayein)

पृष्ठ संख्या: 183

कविता के साथ

1. ‘माटी का रंग’ प्रयोग करते हुए किस बात की ओर संकेत किया गया है?

उत्तर

कविता में ‘माटी के रंग’ का प्रयोग करते हुए झारखंड के संथाल परगना के लोगों की स्वभाविक प्रकृति की ओर संकेत किया गया है| कवयित्री चाहती हैं कि झारखंड के लोगों पर शहरी संस्कृति का प्रभाव न हो तथा उनके व्यवहार में प्रादेशिक गुण बने रहें| उनकी भाषा का झारखंडी स्वभाव नष्ट न हो|

2. भाषा में झारखंडीपन से क्या अभिप्राय है?

उत्तर

झारखंडीपन का अर्थ है झारखंड के लोगों की अपनी भाषा| झारखंड के लोगों की अपनी मूल भाषा है,जिसका विशिष्ट उच्चारण और स्वभाव है| यह उनकी संस्कृति को अलग पहचान प्रदान करता है|

3. दिल के भोलेपन के साथ-साथ अक्खड़पन और जुझारूपन को भी बचाने की आवश्यकता पर बल क्यों दिया गया है?

उत्तर

कवयित्री ने झारखंड के आदिवासियों के अक्खड़पन और जुझारूपन को बचाने की आवश्यकता पर बल दिया है| दिल का भोलापन उनके सरल तथा सहज स्वभाव को दर्शाता है| वे इतने भोले-भाले हैं कि शहरी संस्कृति उन पर गलत प्रभाव डाल सकती हैं| इसलिए कवयित्री चाहती हैं कि सरल स्वभाव के साथ-साथ उनमें अकड़पन भी हों जिससे कि उन्हें सही-गलत की समझ हो सके| कवयित्री उनके जुझारूपन या संघर्षशील स्वभाव को बचाना चाहती हैं ताकि वे कठिन परिस्थितियों में भी लड़ने के काबिल हों|

4. प्रस्तुत कविता आदिवासी समाज की किन बुराइयों की ओर संकेत करती है?

उत्तर

प्रस्तुत कविता में आदिवासी समाज की कई ऐसी बुराइयों का उल्लेख किया गया है जो उनकी संस्कृति को धूमिल कर रहा है-
• उनके जीवन पर शहरी संस्कृति का प्रभाव पड़ रहा है जिसके कारण वे अपनी असली पहचान को भूलते जा रहे हैं|
• संथाली समाज अभी भी अशिक्षित है|
• उनका झुकाव शराब की ओर अधिक हो रहा है|
• उनके अंदर आत्मविश्वास की कमी है|
• धनुष-बाण संथाल परगना की पहचान है| लेकिन आदिवासियों की ये पहचान अब खो चुकी है|

5. इस दौर में भी बचाने को बहुत कुछ बचा है- से क्या आशय है?

उत्तर

कवयित्री ने आज के अविश्वास भरे दौर में भी बचाने को बहुत कुछ बचा है, इसलिए कहा है क्योंकि आज के युग में बढ़ती अविश्वास तथा एक दूसरे के बीच के ईर्ष्या और द्वेष की भावना आदिवासी समाज को पूरी तरह प्रभावित नहीं कर सकी है| इसलिए कवयित्री उनकी भाषा और संस्कृति के गुणों को बचाना चाहती हैं|

6. निम्नलिखित पंक्तियों के काव्य-सौन्दर्य को उद्घाटित कीजिए-

(क) ठंडी होती दिनचर्या में
जीवन की गर्माहट

उत्तर

• कवयित्री ने दिनचर्या में आई नीरसता को दूर करने के लिए ‘गर्माहट’ शब्द का लाक्षणिक प्रयोग किया है|
• छंदमुक्त पंक्तियाँ हैं|
• शब्द प्रतीकात्मक हैं|
• भाषा अत्यंत सरल एवं सहज है|

(ख) थोड़ा-सा अविश्वास
थोड़ी-सी उम्मीद
थोड़े–से सपने
आओ, मिलकर बचाएँ

उत्तर

• भाषा सहज एवं सुबोध है|
• थोड़ा-सा, थोड़ी-सी, थोड़े–से तीनों शब्दों के प्रयोग से कविता में अभिव्यक्ति अच्छी बन पड़ी है|
• अच्छे भविष्य के लिए सभी को मिलकर चलने की प्रेरणा दी गई है|
• कविता प्रेरणादायक है|

7. बस्तियों को शहर की किस आबो-हवा से बचाने की आवश्यकता है?

उत्तर

आदिवासी बस्तियों या समाज को शहरी अपसंस्कृति के प्रभाव से बचाने की आवश्यकता है| शहरों की बढ़ती नग्नता और अश्लीलता आदिवासियों को भी मर्यादाविहीन बना रही हैं| शहरीकरण का प्रभाव बस्तियों को वृक्षविहीन बना रहा है| दिन-प्रतिदिन लोगों की बढ़ती व्यस्तता उनमें अलगावपन को बढ़ावा दे रहा है| इन बस्तियों की अपनी एक विशिष्ट पहचान तथा संस्कृति है जिसे कवयित्री शहर के गलत आबो-हवा से बचाना चाहती हैं|

कविता के आस-पास

1. आप अपने शहर या बस्ती की किन चीजों को बचाना चाहेंगे?

उत्तर

हम अपने शहर या बस्ती को निम्नलिखित चीजों से बचाना चाहेंगे:
• आधुनिक युग की बढ़ती व्यस्तता और जड़ता से बचाना चाहेंगे|
• महानगरों में व्याप्त स्वार्थ की भावना तथा ईर्ष्या-द्वेष से भी अपने समाज या बस्ती को बचाना चाहेंगे|
• शहर की अमर्यादित संस्कृति के कुप्रभाव से भी बचाना चाहेंगे|
• तनाव भरी जिंदगी से बचाना चाहेंगे|

2. आदिवासी समाज की वर्तमान स्थिति पर टिप्पणी करें|

उत्तर

आदिवासियों की वर्तमान स्थिति पहले की तुलना में बहुत हद तक सुधर चुकी है| सरकार ने इनके क्षेत्र में अनेक विकास के कार्यक्रम लागू किए हैं| इन्हें शिक्षित किया जा रहा है जिससे गरीबी और बेरोजगारी की समस्या दूर हुई है| इन्हें अपने अधिकारों के प्रति जागरूक किया जा रहा है| इन क्षेत्रों में यातायात के साधनों का विकास हो चुका है| पुराने रीति-रिवाज और आडंबरों का उन्मूलन किया जा रहा है| वे स्वयं को आधुनिकता के परिवेश में रूपांतरित कर रहे हैं|

Class 11 की आरोह NCERT Solutions की सूची में वापिस जाएँ

Study Material and Notes of Ch 9 Reproduction in Animals Class 8th Science

Topics in the chapter

• Male Reproductive System
• Female Reproductive System
• Fertilization
→ Internal fertilization
→ External Fertilization
• Test tube baby
• Fertilization in Humans
• Asexual reproduction
→ Budding
→ Fission
→ Cloning
• Oviparous animals
• Viviparous animals
• Metamorphosis
• Lifecycle of silkworm
• Hormone responsible for metamorphosis in insects

Male Reproductive System

→ It consists of testis, sperm duct and penis.

→ Testes are involved in the production of male gametes called sperms.

→ Millions of sperms are produced by the testes.

→ Each sperm consists of three parts: Head, middle piece and tail.

Female reproductive system

→ It consists of ovaries, oviduct and uterus.

→ Ovaries produce ova or eggs.

→ A single matured egg is released from ovary into oviduct every month.

→ Baby develops in the uterus.

→ Egg is also single celled like sperm.

Fertilization

→ The process of fusion of male and female gametes (egg and sperm) to form zygote is known as fertilization.

→ It is of two types:
(i) Internal fertilization
(ii) External fertilization

Internal fertilization

→ In this, the fusion of sperm and egg takes place inside the female's body.

→ It occurs in cows, dogs and humans.

External fertilization

→ In this, the fusion of sperm and egg takes place outside the female's body in a surrounding medium, generally water.

→ It occurs in frogs, fishes, starfish, etc.

Test tube baby

→ A baby conceived by fertilization that occurs outside the mother’s body is called test tube baby.

→ Development of the embryo

→ The zygote repeatedly divides to form a ball of cells.

→ The ball of cells then starts differentiating into tissues and organs. At this stage, it is called embryo.

→ Embryo gets attached to the wall of the uterus and develops various body parts such as hands and legs.

→ Foetus is a stage of embryo that shows main recognizable feature of mature organism.

→ Foetus develops for nine months inside the mother’s womb and is finally delivered.

Fertilization in Humans

→ Fusion of the nucleus of the sperm with the ovum to form a zygote. It occurs in the fallopian tube of females.

→ Zygote divides to form an embryo.

→ Embryo is implanted in the uterus.

→ Foetus develops inside the mother’s body for nine months (gestation period).

Asexual reproduction

→ The type of reproduction which involves only a single parent and the new individuals are formed without the fusion of gametes is known as asexual reproduction.

• Three common methods of asexual reproduction are:
(i) Budding
(ii) Fission
(iii) Cloning

Budding

→ It involves the formation of new individual from the bulging of the parent body.

→ This phenomenon is very common in plants, fungi and animals such as Hydra and yeast.

Fission

→ Binary fission is the type of asexual reproduction that occurs in Amoeba.

→ It is a type of asexual reproduction in which a single cell divides into two halves.

Cloning

→ Cloning is the process used to create an exact copy of a cell, tissue or an organism.

→ Dolly, a sheep was the first mammal to be cloned. It was cloned by Ian Wilmut and his colleagues in 1996.

Oviparous animals

→ The animals that lay eggs are called oviparous animals.

→ The examples include all kinds of birds, lizards, snakes, and frogs.

Viviparous animals

→ The animals that give birth to young ones are called viviparous animals.

→ The examples include cows, dogs, and humans.

Metamorphosis

→ The biological process of transformation of larva into an adult is known as metamorphosis.

• The life cycle of frog consists of the following stages:
Egg → Tadpole (larva) → Adult

→ Hormones controlling metamorphosis in frogs

→ Thyroxin (produced by the thyroid gland) initiates the process of a tadpole’s metamorphosis into an adult frog.

→ In the absence of thyroxin, the tadpole does not transform into an adult and remains in the tadpole stage.

Life cycle of silkworm

→ Silkworm grows on mulberry trees and feeds on its leaves.

→ During a stage in its life cycle, silkworm spins a cocoon around itself.

→ Silk is obtained from this cocoon.

Hormone responsible for metamorphosis in insects

→ In insects, metamorphosis is controlled by the insect hormones. Some of the insect hormones are:
(i) Prothoracicotropic Hormone (PTTH)
(ii) Ecdysone
(iii) Juvenile Hormone (JH)

Study Material and Notes of Ch 10 Reaching the Age of Adolescence Class 8th Science

Topics in the chapter

• Adolescence
• Puberty
→ Increase in height
→ Change in body shape
→ Change in the voice pattern
→ Change in activity of sweat and sebaceous glands
→ Change in sex organs
→ Change in intellectual level
• Secondary sexual characteristics in boys
• Secondary sexual characteristics in girls
• Hormones
→ Characteristics of hormones
• Endocrine glands
→ Pituitary gland
→ Thyroid gland
→ Parathyroid gland
→ Pancreas
→ Adrenal gland
• Gonads
• Historical background and discovery of HIV
→ Structure of HIV
→ Transmission of HIV
→ Prevention of HIV
→ Tests for detection of HIV
• Personal health and hygiene in adolescents
• Sex determination in humans

Adolescence

→ The time period when the body undergoes changes to reach reproductive maturity is known as
adolescence.

→ It begins around the age of 11 and lasts till about 18 or 19 years of age.

→ Adolescence in girls can begin one or two years earlier than boys.

Puberty

→ The various changes that occur in the body during adolescence marks the onset of puberty.

→ Puberty ends when teenagers attain sexual maturity.

→ Changes that take place during puberty

Increase in height

→ It is caused by the growth in long bones of the arms and legs.

→ Girls grow faster than boys initially but both reach their maximum height by the age of 18
years.

Change in body shape

→ Boys develop broader shoulders, wider chests, and prominent muscles.
→ In girls the region below the waist becomes wider.

Change in the voice pattern

→ Voice box or larynx starts growing during puberty.

→ It protrudes in males in the neck region and is called Adam’s apple.

→ Boys develop deep low-pitched voice.

→ Girls develop high-pitched voice.

Change in activity of sweat and sebaceous glands

→ The activity of sweat glands increases during puberty, resulting in production of more sweat.

→ The oily secretions from sebaceous glands increase. The accumulation of oil and bacterial action leads to acne problems in teenagers.

Changes in sex organs

→ Testes and penis develop completely in boys.

→ Testes start producing sperms.

→ Ovaries develop completely and start producing eggs in girls.

Change in intellectual level

→ The learning capacity of brain increases.

→ Intellectual development takes place during adolescence.

→ Development of secondary sexual characteristics.

Secondary sexual characteristics in boys

→ Appearance of moustaches and beard.

→ Appearance of hair on chest.

→ Growth of hair in genital area and other parts.

Secondary sexual characteristics in girls

→ Increase in breast size

→ Growth of hair in the pubic region.

Hormones

→ Hormones are chemical secretions that bring about various changes in the body.

→ They are produced by endocrine glands.

→ These glands release hormones into blood to reach specific target site.

→ Production of hormones is under the control of hormones produced from pituitary gland.

Characteristics of hormones

→ Hormones act as chemical messengers.

→ They are secreted by living cells/tissues or organs called glands.

→ They are secreted in very small quantities by glands.

→ They act upon specific cells, tissues, or organs called the target sites.

→ They are generally slow in action, but have long lasting effects.

→ They either accelerate or inhibit a reaction.

Endocrine glands

→ Hormones are secreted by endocrine glands such as the pituitary gland, thyroid gland, adrenal gland, pancreas etc.

• Major endocrine glands in humans are

(i) Pituitary
(ii) Hypothalamus
(iii) Pineal
(iv) Thyroid
(v) Parathyroid
(vi) Thymus
(vii) Pancreas
(viii) Adrenal
(ix) Testis in men /ovary in women

→ A feedback mechanism (positive and negative) regulates the action of the hormones.

Pituitary gland

→ It is a pea sized gland situated at the base of the brain. It secretes a growth hormone (GH).

→ It is required for proper body growth.

→ The hyposecretion of growth hormone causes a condition called dwarfism.

→ The hypersecretion causes gigantism in children and acromegaly in adults.

Thyroid gland

→ It is located close to trachea in the neck. It produces a hormone called thyroxine.

→ It is required for regulating metabolism in the body.

→ The hyposecretion of thyroxine causes hypothyroidism.

→ This condition causes abnormalities like simple goitre, myxoedema and cretinism.

→ Lack of iodine leads to deficiency of thyroxine, which results in a disease called goitre.

→ The excess secretion of thyroxine causes hyperthyroidism. It results in high metabolism, protrusion of the eye balls, high BP, nervous tension, etc.

Parathyroid Gland

→ There are four parathyroid glands present on back side of thyroid glands that secrete parathyroid hormone or parathormone (PTH).

→ This hormone regulates the level of calcium ions in the bloodstream.

→ Excess of parathyroid hormone removes calcium from bones and makes them soft.

Pancreas

→ It produces two hormones- Insulin and Glucagon.

→ These hormones maintain blood sugar level.

→ Deficiency of insulin results in diabetes.

Adrenal Gland

→ There are two adrenal glands located one on upper part of each kidney.

→ It has two parts- cortex and medulla.

→ Cortex secretes the hormones like cortisol that regulates the rate of metabolism.

→ The medulla secretes a hormone like adrenaline that prepares the body to face various stressful situations.

Gonads

→ It includes testes in males and ovaries in females.

→ Male sex hormone is testosterone. It is produced by the testes on the onset of puberty.

→ Female sex hormones produced by ovaries are estrogen and progesterone.

→ Deficiency of estrogen causes infertility.

→ Process of Hormonal Action

→ Endocrine glands release their secretions (hormones) into the bloodstream.

→ Hormones, on reaching their target site, bring about necessary changes to maintain proper functioning of the body.

Historical background and Discovery of HIV

→ The first cases of AIDS were recognized in U.S.A in the year 1981.

→ The AIDS virus was first discovered by the team of French scientists lead by Luc Montagnier in1983.

→ In 1984, the American virologist named Robert Charles Gallo gave the first report on the virus causing AIDS.

→ The name HIV was suggested by the International committee on the nomenclature of viruses.

→ In India the firsts AIDS patient was identified in Chennai in the year 1987.

→ AIDS or Acquired Immune deficiency syndrome is a viral disease, caused by the deadly virus (HIV).

Structure of HIV

→ Human Immunodeficiency virus (HIV) is spherical in shape and contains RNA as its genetic material.

→ Externally, the virus is covered by the double layered membrane made up of fatty substances.

→ Inside the fatty membrane a core of proteins is found that surrounds the viral RNA along with the enzyme reverse transcriptase.

Transmission of HIV

→ Sharing of syringes during drug abuse.

→ Unsafe sexual contact.

→ Transfusion of infected blood

→ From infected mother to her infant through milk.

Prevention of HIV

→ Avoid sexual contact with infected persons

→ Ensure use of disposable syringes

→ Screening blood from blood banks

Tests for detection of HIV

→ PCR (Polymerase Chain Reaction)

→ ELISA (Enzyme linked Immuno Sorbent Assay)

→ Western Blot

Personal health and hygiene in adolescents

→ Adolescents should have a balanced diet with right proportions of various nutrients.

→ Adolescents should maintain cleanliness to prevent bacterial infections.

→ They should indulge in some physical exercises to keep their bodies fit.

→ They should avoid the consumption of drugs and alcohol.

Sex determination in humans

• Autosomes: First 22 pairs of chromosomes that do not determine the sex of an individual.

• Sex chromosomes: Last pair of chromosomes, represented as X and Y.

→ Females have two X chromosomes,so can be represented as 44+XX.

→ Males have one X and one Y chromosome, so can be represented as 44+XY.

→ Each gamete receives half of the chromosomes i.e. 22+X or 22+Y.

→ Male gametes have 22 autosomes and either X or Y sex chromosome.

→ Male gametes can be of two types, 22+X or 22+Y.

→ Female gametes can be of only one type, 22+X.

→ Sex of a baby is determined by the type of the male gamete (X or Y) that fuses with the female gamete.

पठन सामग्री, अतिरिक्त प्रश्न और उत्तर और सार - पाठ 20 - आओ मिलकर बचाएँ (Aao milkar bachayein) आरोह भाग - 1 NCERT Class 11th Hindi Notes

सारांश

संथाल समाज में जहाँ एक ओर सादगी, भोलापन, प्रकृति से जुड़ाव और कठोर परिश्रम करने की क्षमता जैसे सकारात्मक तत्व हैं, वहीँ दूसरी ओर उसमें अशिक्षा, कुरीतियाँ और शराब की ओर बढ़ता झुकाव भी है| प्रस्तुत कविता ‘आओ मिलकर बचाएँ’ में दोनों पक्षों का यथार्थ चित्रण हुआ है| प्रकृति के विनाश और विस्थापन के कारण आज आदिवासी समाज का संकट में है, जो कविता का मूल स्वर है|

कवयित्री झारखंड की आदिवासी संस्कृति को शहरी सभ्यता के कुप्रभाव से दूर रखना चाहती हैं| वह तेजी से हो रहे शहरीकरण के कारण अपने प्रदेश को वृक्षविहीन होने से बचाना चाहती हैं| शहरी उच्छृंखलता आदिवासियों के सरल और सहज स्वभाव को प्रभावित कर रही है| कवयित्री चाहती हैं कि आदिवासी समाज के जीवन में उत्साह, जोश, भोलापन, अक्खड़पन तथा जुझारूपन बना रहे, जो झारखंडी संस्कृति की पहचान है| वे धनुष-बाण तथा कुल्हाड़ी को धारण कर अपनी सभ्यता की पहचान बनाए रखें| झारखंड के पर्वतों की शांति, नदियों का शोर, पहाड़ी गीतों का धुन उसे एक अलग विशिष्टता प्रदान करते हैं| वह चाहती हैं कि संथाल परगना की मिट्टी की सुगंध तथा उन पर लहलहाती फसलें ज्यों की त्यों बनी रहे| उन पर शहरी जीवन का प्रभाव न पड़े| कवयित्री के अनुसार वर्तमान युग में आपसी संदेह का वातावरण छाया हुआ है और लोगों में ईर्ष्या-द्वेष की भावना बढ़ रही है| वह चाहती हैं कि उनका संथाल समाज इन बुराइयों से बचा रहे तथा उनकी स्वाभाविक सहजता तथा संवेदनशीलता बनी रहे| इस प्रकार वह मनुष्य-जीवन के बीच घटते अविश्वास, आस्था, आशा आदि को बचाकर अपने आदिवासी संस्कृति को धूमिल होने से बचाना चाहती हैं|

कवयित्री-परिचय

निर्मला पुतुल

जन्म - सन् 1972, दुमका (झारखंड) में|

प्रमुख रचनाएँ - नगाड़े की तरह बजते शब्द, अपने घर की तलाश में|

इनका जन्म एक आदिवासी परिवार में हुआ| इनका आरंभिक जीवन बहुत संघर्षमय रहा| घर में शिक्षा का माहौल होने के बावजूद रोटी की समस्या से जूझने के कारण नियमित अध्ययन बाधित होता रहा| उन्होंने नर्सिंग में डिप्लोमा करने के बाद इग्नू से स्नातक की डिग्री प्राप्त की| संथाली समाज और उसके राग-बोध से गहरा जुड़ाव पहले से था, नर्सिंग की शिक्षा के समय बाहर की दुनिया से भी बाहर की दुनिया से भी परिचय हुआ|

उन्होंने आदिवासी समाज की विसंगतियों को को तल्लीनता से उकेरा है- कड़ी मेहनत के बावजूद खराब दशा, कुरीतियों के कारण बिगड़ती पीढ़ी, थोड़े लाभ के लिए बड़े समझौते, पुरूष वर्चस्व, स्वार्थ के लिए पर्यावरण की हानि, शिक्षित समाज की दिक्कुओं और व्यवसायियों के हाथों की कठपुतली बनना आदि वे स्थितियाँ हैं जो पुतुल की कविताओं के केंद्र में है|

कठिन शब्दों के अर्थ

• आबो-हवा- जलवायु
• माटी- मिट्टी
• सोंधापन- सुगंध
• उम्मीद- आशा
• दौर- समय
• अक्खड़पन- किसी बात को लेकर रुखाई से तन जाने का भाव
• जुझारूपन- जूझने या संघर्ष करने की प्रवृत्ति

NCERT Solutions of पाठ 20 - आओ, मिलकर बचाएँ

NCERT Solutions for Class 12th: Ch 8 Transport and Communication Fundamentals of Human Geography

Exercises

Page No: 80

1. Choose the right answer from the four alternatives given below.

(i) The Trans–Continental Stuart Highway runs between
(a) Darwin and Melbourne
(b) Edmonton and Anchorage
(c) Vancouver and St. John’s City
(d) Chengdu and Lhasa
► (a) Darwin and Melbourne

(ii) Which country has the highest density of railway network?
(a) Brazil
(b) U.S.A

(d) Russia
► (b) U.S.A

(iii) The Big Trunk Route runs through
(a) The Mediterranean – Indian ocean
(b) The North Atlantic Ocean
(c) The South Atlantic Ocean
(d) The North Pacific Ocean
► (b) The North Atlantic Ocean

(iv) The Big Inch pipeline transports
(a) Milk
(b) Liquid petroleum gas (LPG)

(d) Petroleum
► (d) Petroleum

(v) Which one pair of the following places is linked by Channel Tunnel?
(a) London – Berlin
(b) Paris – London

(d) Barcelona – Berlin
► (b) Paris – London

2. Answer the following questions in about 30 words.

(i) What are the problems of road transport in mountainous, desert and flood prone regions?

Answer

The problems of road transport in mountainous, desert and flood prone regions are:

• In mountainous regions, there is steep slope and unlevelled patterns which make difficult to construct roads. The construction and maintenance of roads are very high.

• In deserts, constructing roads is difficult due to excessive sand. Scarce vegetation and low density of population do not encourage roads.

• In flood prone areas, roads get damaged frequently.

(ii) What is a trans–continental railway?

Answer

Trans–continental railways run across the continents and links two ends. They were constructed for economic and political reasons to facilitate long runs in different directions.

(iii) What are the advantages of water transport?

Answer

There are various advantages of water transport:

• It does not require route construction. The oceans are linked with each other and provide passages to ships of various sizes.

• It is much cheaper because the friction of water is far less than that of land. The energy cost of water transportation is lower.

• It is useful for the transportation of heavy and bulky goods.

3. Answer the following questions in not more than 150 words.

(i) Elucidate the statement– “In a well managed transport system, various modes complement each other”.

Answer

In a well managed transport system, various modes do not compete with each other but complement each other.
• Railways are more useful for moving bulky goods and passengers over long distances while Roadways are suitable for the faster movement over shorter distances and door-to-door services. They also act as feeder transport to railways.
• When urgent and faster movement required then air transport is the most appropriate option.
• International movement of bulky goods can be possible through ocean routes.
• Railways also serve ports so that goods can move faster and more cheaply.
• For crossing seas and mountains more faster we can use air tranposrt.
• Liquids and gases such as water, petroleum and natural gas can be transported better through pipelines than all other means of transport.

(ii) Which are the major regions of the world having a dense network of airways.

Answer

• Air Transport is the only means to reach mountainous snow fields or desert terrains.

• At present no place in the world is more than 35 hours away. This startling fact has been made possible due to people who build and fly airplanes.

• Frequent air services are available to many parts of the world. Although, U.K. pioneered the use of commercial jet transport, U.S.A. developed largely post-War international civil aviation.

• Today, more than 250 commercial airlines offer regular services to different parts of the world.

• Dense network exists in Eastern U.S.A., Western Europe and South East Asia. U.SA. alone accounts for 60 per cent of the airways of the world. New York, London, Paris, Amsterdam, Frankfurt, Rome, Moscow, Karachi, New Delhi, Mumbai, Bangkok, Singapore, Tokyo, San Francisco, Los Angeles and Chicago are the nodal points where air routes converge or radiate to all continents. Africa, Asiatic part of Russia and South America lack air services.

(iii) What are the modes by which cyber space will expand the contemporary economic and social space of humans.

Answer

The modes by which cyber space will expand the contemporary economic and social space of humans are:

• e-mail - Electornic mail is a method of exchanging messages between people using electronics. These are delivered extremely fast when compared to traditional post thus, widely accepted by business, governments and non-governmental organizations in the developed world. Each email has the date and time recorded on it which is helpful in avoding confusion and dispute.

• e-commerce: It is a transaction of buying or selling online. It can take place 24 hours a day, seven days a week and can provide wide variety of options than traditional stores. The customer can order the product of their choice and get it delivered to their home.

• e-learning: It is the use of technology to enable people to learn anytime and anywhere. It can include training, the delivery of just-in-time information and guidance from experts. Knowledge can also be shared via the Internet, which is accessible 24/7, anywhere, anytime.

• e-governance: It is a style of governance in which information and communication technology (ICT) is applied for achieving the results. Through e-governance, government services will be made available to citizens in a convenient, efficient and transparent manner.

Go to Index of Class 12th Fundamentals of Human Geography NCERT Solutions

Study Material and Notes of Ch 11 Force and Pressure Class 8th Science

Topics in the chapter

• Introduction
• Force
→ Push
→ Pull
• Muscular Force
• Friction
• Magnetic Force
• Electrostatic Force
• Gravitational Force
• Pressure
• Fluid
• Atmospheric Pressure

Introduction

→ Actions like picking, opening, shutting, kicking, hitting, lifting, flicking, pushing, pulling are often used to describe certain tasks.

→ Each of these actions usually results in some kind of change in the motion of an object.

Force

→ A push or pull on an object is called a force.

• Push: When an object is moving away from the applier of force.

• Pull: When an object is moving towards the applier of force.

→ Force is a push or a pull which changes or tends to change the state of rest or of uniform motion, or direction of motion or the shape or size of a body.

→ Force is any action that has the tendency to change the position, shape, or size of an object.

→ Interaction of one object with another object results in a force between the two objects.

→ The effect of force depends on the magnitude and direction of the force.

→ Force applied in the same direction added to one another.

→ Force applied in the opposite direction, the net force is given by the difference of two forces.

→ Force can move a body initially at rest.

→ Force can bring a moving body to rest.

→ Force can change the direction of a moving body.

→ Force can change the speed of a moving body.

→Force can change the shape of a body.

→ Force can change the size of a body.

Muscular force

→ It involves the action of muscles.

→ Animals make use of muscular force to carry out their physical activities and other tasks.

Friction

→ It is an opposing force that acts between surfaces in contact moving with respect to each other.

→ The direction of force of friction is always opposite to the direction of motion.

→ Frictional force always acts between two moving objects, which are in contact with one another.

→ Frictional force always acts opposite to the direction of motion.

→ Frictional force depends on the nature of the surface in contact.

→ Non-contact force come into play even when the bodies are not in contact.

Magnetic force

→ Force acting between two magnets or a magnet and a magnetic material.
Example: iron, steel, nickel, cobalt etc.).

→ It can be attractive and repulsive.

Electrostatic force

→ Force due to electric charges.

→ It can be attractive and repulsive.

Gravitational force

→ It is a kind of attractive force that comes into play because of the mass of a body.
Example: earth's gravitational attraction.

Pressure

→ The force acting per unit area of surface is called pressure.

• Pressure = Force/Area on which it acts

→ The unit of pressure is Newton per square meter (N/m²), which is also known as Pascal.

→ Smaller the area larger the pressure for the same force.

→ Liquids exerts pressure on the walls of the container.

→ Pressure exerted by liquids increases with depth.

→ Liquids exert equal pressure at the same depth.

→ The pressure at which water comes out of the holes is directly proportional to its depth.

Fluid

→ Substance which can flow and has no fixed shape

• Pressure due to a liquid column of height h (p) = hrg

where, h = Height of column
r = Density of fluid
g = Acceleration due to gravity

→ Pressure inside a fluid increases with increase in depth and density of the fluid.

→ Water and gas exert pressure on the walls of their container.

→ Atmosphere exerts pressure on the surface of the Earth.

• Atmospheric pressure = Weight of the atmosphere per unit area.

Pressure inside our body is equal to the atmospheric pressure and cancels the pressure from out side.

Air surrounding the Earth: atmosphere

Air exerts pressure on its surroundings: thrust on unit area is called atmospheric pressure

Study Material and Notes of Ch 12 Friction Class 8th Science

Topics in the chapter

• Introduction
• Friction
→ Causes of Friction
→ Nature of surfaces of Friction
→ Friction when object is pressed hard
→ Friction according to mass of object
→ Examples where friction is useful
→ Examples where friction is harmful
• Rolling Friction
• Sliding Friction
• Fluid Friction

Introduction

→ The vehicles, any object, moving over the surface of another object slows down due to the force of friction applied on it.

Friction

→ It is an opposing force that acts between surfaces in contact moving with respect to each other.

→ It always opposes relative motion between two surfaces.

Cause of friction

→ Friction is cause by the irregularities on the two surfaces in contact.

→ We are able to walk because of the force of friction.

Nature of surfaces for Friction

Smooth surfaces: less friction
Rough surfaces: greater friction

Friction when object is pressed hard

Greater pressing force means Greater friction.

Friction according to mass of object

Greater mass: Greater friction

Sliding friction < Static friction
Rolling friction < Sliding friction

Examples where friction is useful

(i) Walking
(ii) Handling any object
(iii) Rolling motion of ball or wheel

Examples where friction is harmful

(i) Energy dissipation of engine due to friction between surfaces in motion.
(ii) More energy is lost in pulling or pushing an object in rough surfaces.
(iii) Wear and tear of shoe soles and tyres.

(iv) Lubrication: Powder on carom board, oil in machine
(v) Wheel: Wheels reduce friction (because rolling friction < sliding friction).
(vi) Shoe soles and tires are threaded to increase friction for a better grip.
(vii) Fluid friction is minimised by giving suitable shapes to vehicles moving through fluids.

Rolling Friction

→ When a body rolls over the surface of another body, the resistance to its motion is called rolling friction.

Sliding Friction

→ When a body slides over the surface of another body, the resistance to its motion is called sliding friction.

• Rolling friction < Sliding friction

→ Ball bearings change sliding friction into rolling friction.

Fluid Friction

→ Fluid friction is minimised by giving suitable shapes to vehicles moving through fluids.

• Fluid friction is also called drag.

→ Friction force depends upon the speed of the object with respect to the fluid.

→ Friction force depends upon the shape of the and nature of the fluid.

NCERT Solutions for Class 12th: Ch 9 International Trade Fundamentals of Human Geography

Exercises

Page No: 80

1. Choose the right answer from the four alternatives given below.

(i) Most of the world’s great ports are classified as:
(a) Naval Ports
(b) Oil Ports
(c) Comprehensive Ports
(d) Industrial Ports
► (c) Comprehensive Ports

(ii) Which one of the following continents has the maximum flow of global trade?
(a) Asia
(b) North America
(c) Europe
(d) Africa
► (c) Europe

(iii) Which one of the following South American nation, is a part of OPEC?
(a) Brazil
(b) Chile

(d) Peru

► (c) Venezuela

(iv) In which of the following trade blocs, is India an associate member?
(a) SAFTA
(b) OECD

(d) OPEC

► (c) ASEAN

2. Answer the following questions in about 30 words:

(i) What is the basic function of the World Trade Organisation?

Answer

The basic functions of the World Trade Organisation:

• WTO deals with the global rules of trade between nations.

• It sets the rules for the global trading system and resolves disputes between its member nations.

• WTO also covers trade in services, such as telecommunication and banking, and others issues such as intellectual rights.

(ii) Why is it detrimental for a nation to have negative balance of payments?

Answer

A negative balance would mean that the country spends more on buying goods than it can earn by selling its goods. This would ultimately lead to exhaustion of its financial reserves.

(iii) What benefits do nations get by forming trading blocs?

Answer

Regional Trade Blocs have come up in order to encourage trade between countries with geographical proximity, similarity and complementarities in trading items and to curb restrictions on trade of the developing world.

3. Answer the following questions in not more than 150 words:

(i) How are ports helpful for trade? Give a classification of ports on the basis of their location.

Answer

Ports are chief gateways of the world of international trade are the harbours and ports. Cargoes and travellers pass from one part of the world to another through these ports.

The ports provide facilities of docking, loading, unloading and the storage facilities for cargo. In order to provide these facilities, the port authorities make arrangements for maintaining navigable channels, arranging tugs and barges, and providing labour and managerial services.

Types of port on the basis of location:

(i) Inland Ports: These ports are located away from the sea coast. They are linked to the sea through a river or a canal. Such ports are accessible to flat bottom ships or barges. For example, Manchester is linked with a canal; Memphis is located on the river Mississippi; Rhine has several ports like Mannheim and Duisburg. a branch of the river Ganga.

(ii) Out Ports: These are deep water ports built away from the actual ports. These serve the parent ports by receiving those ships which are unable to approach them due to their large size. Classic combination, for example, is Athens and its out port Piraeus in Greece.

(ii) How do nations gain from International Trade?

Answer

International trade is the exchange of goods and services among countries across national boundaries. Countries need to trade to obtain commodities, they cannot produce themselves or they can purchase elsewhere at a lower price.

• International trade is the result of specialisation in production.

• It benefits the world economy if different countries practise specialisation and division of labour in the production of commodities or provision of services.

• Each kind of specialisation can give rise to trade. Thus, international trade is based on the principle of comparative advantage, complimentarity and transferability of goods and services and in principle, should be mutually beneficial to the trading partners.

Go to Index of Class 12th Fundamentals of Human Geography NCERT Solutions

NCERT Solutions for Class 12th: Ch 10 Human Settlements Fundamentals of Human Geography

Exercises

Page No: 101

1. Choose the right answer from the four alternatives given below.

(i) Which one of the following forms of settlement develops along either side of roads, rivers or canals?
(a) circular
(b) linear

(d) square

► (b) linear

(ii) Which one of the following types of economic activities dominates in all rural settlement?
(a) primary
(b) tertiary

(d) quaternary

► (a) primary

(iii) In which of the following regions has the oldest well-documented urban settlement found?
(a) Huang He Valley
(b) Indus Valley

(d) Mesopotamia

► (d) Mesopotamia

(iv) How many of the following cities in India have attained the million status at the beginning of 2006?
(a) 40
(b) 42

(d) 43

► (b) 42

(v) Sufficiency of which type of resources can help to create adequate social infrastructure catering to the needs of the large population in the developing countries?
(a) financial
(b) human

(d) social

► (c) natural

Page No: 102

2. Answer the following questions in about 30 words.

(i) How would you define a settlement?

Answer

A human settlement is defined as a place inhabited more or less permanently. There may be some settlements which are temporary and are occupied for short periods, maybe a season.

(ii) Distinguish between site and situation.

Answer

Site	Situation
Site means the actual piece of land on which the settlement is built.	Situation means the location of the village or town in relation to surrounding areas.
Site for settlement may be a hill top, a river bank or a coast of sea.	Situation may be studies in relation to the physical environment and cultural heritage.
Proper site for a settlement is generally determined by its access to water and other amenities for sustenance.	The mode of settlement in any particular region reflects human perception of natural environment.

(iii) What are the bases of classifying settlements?

Answer

Settlements can be classified on the basis of:
• Population Size
• Functions of the Settlement
• Occupation of the people
• Facilities in the Settlement

(iv) How would you justify the study of human settlements in human geography?

Answer

The study of settlement is essential and basic to human geography because the form of settlement in any particular region reflects the human relationship with the environment.

3. Answer the following questions in not more than 150 words.

(i) What are rural and urban settlements? Mention their characteristics.

Answer

Rural settlements are most closely and directly related to land. They are dominated by primary activities such as agriculture, animal husbandary, fishing etc.

Characteristics of Rural Settlements:

• Most people are engaged in agriculture, fishing and other primary activities.
• These are smaller in size.
• These lack the modern facilities.
• The density of population is not very high.
• People participate in cultural activities.

Urban settlements are densely populated area in which people are engaged in secondary and tertiary activities mainly.

Characteristics of Urban Settlements:

• Most people are engaged in secondary and tertiary activities.
• These settlements are well planned.
• Urban settlements are large in size.
• The density of population is high.
• These areas have got complex culture because of mixing of other cultures in it.
• They have modern facilities of roads, electricity, water supply etc.

(ii) Discuss the problems associated with urban settlements in developing countries.

Answer

The various problems associated with urban settlements in developing countries are:

• People flock to cities to avail of employment opportunities and civic amenities. Since most cities in developing countries are unplanned, it creates severe congestion.

• Shortage of housing, vertical expansion and growth of slums are characteristic features of modern
cities of developing countries. In many cities an increasing proportion of the population lives in substandard housing, e.g. slums and squatter settlements.

• Cities in the developing countries suffer from several social ills. Insufficient financial resources
fail to create adequate social infrastructure catering to the basic needs of the huge population. The available educational and health facilities remain beyond the reach of the urban poor.

• The large urban population in developing countries not only uses but also disposes off a huge quantity of water and all types of waste materials.

• Many cities of the developing countries even find it extremely difficult to provide the minimum required quantity of potable water and water for domestic and industrial uses. An improper sewerage system creates unhealthy conditions.

Go to Index of Class 12th Fundamentals of Human Geography NCERT Solutions

NCERT Solutions for Class 12th: Ch 1 Population Distribution, Density, Growth and Composition India People and Economy

Exercises

Page No: 13

1. Choose the right answer from the four alternatives given below.

(i) India’s population as per 2011 census is :
(a) 1028 million
(b) 3182 million

(d) 1210 million
► (a) 1028 million

(ii) Which one of the following states has the highest density of population in India?
(a) West Bengal
(b) Kerala
(c) Uttar Pradesh
(d) Punjab
► (a) West Bengal

(iii) Which one of the following states has the highest proportion of urban population in India according to 2011 Census?
(a) Tamil Nadu
(b) Maharashtra
(c) Kerala
(d) Goa
► (b) Maharashtra

(iv) Which one of the following is the largest linguistic group of India?
(a) Sino – Tibetan
(b) Indo – Aryan
(c) Austric
(d) Dravidian
► (b) Indo – Aryan

2. Answer the following questions in about 30 words.

(i) Very hot and dry and very cold and wet regions of India have low density of population. In this light, explain the role of climate on the distribution of population.

Answer

Climate plays a very important role in influencing population. The two elements of climate, rainfall and temperature play the most important role in determining the population of an area.
When a place has extremes of climate, the density of population is low such as too cold climate of Himalayas, and the too hot and dry climate of the Thar Desert. When a place has moderate climate, it attracts people and has high density of population.
Rainfall supplies water for agriculture which is the main occupation of Indian people. The amount of rainfall decreases as we move from the Ganga-Brahmaputra Delta in the east towards the Thar Desert in the west.

(ii) Which states have large rural population in India? Give one reason for such large rural population.

Answer

The states like Bihar and Sikkim have very high percentage of rural population. The reason is both states Bihar and Sikkim are highly dependent on agriculture for their livelihood.

(iii) Why do some states of India have higher rates of work participation than others?

Answer

In India, the work participation rate are higher in the areas of lower levels of economic development since number of manual workers are needed to perform the subsistence or near subsistence economic activities

(iv) ‘The agricultural sector has the largest share of Indian workers.’ – Explain.

Answer

About 54.6 per cent of total working population are cultivators and agricultural labourers, whereas only 3.8% of workers are engaged in household industries and 41.6 % are other workers including nonhousehold industries, trade, commerce, construction and repair and other services.

3. Answer the following questions in about 150 words.

(i) Discuss the spatial pattern of density of population in India.

Answer

Density of population, is expressed as number of persons per unit area. It helps in getting a better understanding of the spatial distribution of population in relation to land. The density of population in India is 382 persons per sq km.

• The spatial variation of population densities in the country ranges from as low as 17 persons per sq km in Arunachal Pradesh to 11,320 persons in the National Capital Territory of Delhi.

• Among the northern Indian States, Bihar (1106), West Bengal (1028) and and Uttar Pradesh (829) have higher densities, while Kerala (860) and Tamil Nadu (555) have higher densities among the peninsular Indian states.

• States like Assam, Gujarat, Andhra Pradesh, Haryana, Jharkhand, Odisha have moderate densities.

• The hill states of the Himalayan region and North eastern states of India (excluding Assam) have relatively low densities while the Union Territories (excluding Andaman and Nicobar islands) have very high densities of population.

(ii) Give an account of the occupational structure of India’s population.

Answer

The occupational structure of a country refers to the division of its work force engaged in different economic activities.

• India have a large proportion of primary sector workers compared to secondary and tertiary sectors.

• About 54.6 percent of total working population are cultivators and agricultural labourers, whereas only 3.8% of workers are engaged in household industries and 41.6 % are other workers including nonhousehold industries, trade, commerce, construction and repair and other services.

• As far as the occupation of country’s male and female population is concerned, male workers outnumber female workers in all the three sectors.

• The number of female workers is relatively high in primary sector, though in recent years there has been some improvement in work participation of women in secondary and tertiary sectors.

• The proportion of workers in agricultural sector in India has shown a decline over the last few decades (58.2% in 2001 to 54.6% in 2011).

• Consequently, the participation rate in secondary and tertiary sector has registered an increase. This indicates a shift of dependence of workers from farmbased occupations to non-farm based ones, indicating a sectoral shift in the economy of the country.

Go to Index of Class 12th India People and Economy (Geography) NCERT Solutions

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