NCERT Solutions for Class 6 Science Chapter 9 The Living Organisms and Their Surroundings

Class 6 

Chapter 9 

The Living Organisms and Their Surroundings

1. What is a habitat?
Ans: The surroundings where animals live is called their habitat. The organisms depend on their habitat for their food, water, air, shelter and other needs. Habitat means a dwelling place.

2. How are cactus adapted to survive in a desert?
Ans: Cactus are adapted to survive in a desert as they have

(i) Spiny leaves to prevent water loss through transpiration.
(ii) Stem is modified in such a way that it performs photosynthesis and conserves water.
(iii) Their roots go very deep into the soil for absorbing water.

3. Fill in the blanks:
(a) The presence of specific features which enables a plant or an animal to live in a particular habitat is called adaptation.
(b) The habitats of the plants and animals that live on land are called terrestrial habitats.
(c)The habitats of plants and animals that live in water are called aquatic habitats.
(d) Soil, water and air are the abiotic factors of a habitats.
(e) Changes in our surroundings that make us respond to them are called stimuli.

4. Which of the things in the following list are non-living?

Plough, Mushrooms, Sewing machine, Radio, Boat, Water, Hyacinth, Earthworm. 

Ans: Plough, Sewing machine, Radio, Boat and water are non-living.

5. Give an example of a non-living thing which shows any two characteristics of living thing.
Ans: Example of non-living thing is cloud which shows following two characteristics of living things:
(i) It grows in size
(ii) It shows movement.

6. Which of the following non-living things were once part of a living thing?

Butter, Leather, Soil, Wool, Electric Bulb, Cooking Oil, Salt, Apple, Rubber.
Ans: Butter, Leather, Wool, Cooking oil, Apple and Rubber are the non-living things which were once part of a living thing.

7. List the common characteristics of living things.
Ans: Some common characteristics of living things are:

• Growth
• Movement
• Reproduction
• Respiration
• Responsiveness
• Excretion

8. Explain why speed is important for survival in the grasslands for animals that live there. (Hint: There are few trees or places for animals to hide in grasslands habitats).
Ans: In grasslands habitats, there are few trees or places for animals to hide. When their enemy attacks they have to run faster so as to reach a safe place. If they fail, they lose their life. So, the speed is very important for survival of grassland animals. 

Class 6 Science-Workbook Chapter 8 Body Movements

 Chapter 8

Body Movements

Exercise

I. Answer the following questions in brief:

Q. 1. What is the use of joints in our body?

Ans - A joints are the part of the body where two or more bones meet to allow movement.

Q.2. Are all joints movable? If not, given an example?

Ans - No some joints are not movable. Example - The Fixed joint of our skull,

Q. 3. Which bones do the ribs join?

Ans - The ribs join with the backbone.

Q.4. What is the use of our backbone having a large number of bones joined together instead of being a single bone?

Ans - A large number of bones in our backbone help us to bend our body.

Q.5. Name the joint present in our (i) neck (ii) knee

Ans  (i) Neck: Pivot Joint  (ii) Knee: Hinge Joint

Q.6. Name any two organs which the rib cage protects.

Ans (a) Heart   (b) Lungs

Q.7. What are the upper parts of human ears made up of ? Where else is this substance found in our body?

Ans - The upper parts of human ears are made up of cartilage. It is also found in the joints of the body.

Q.8. What changes occur in a muscle when it contracts?

Ans - Muscular contractions are the mechanism that allows an individual, animal, or human to move its body, move the food in its digestive. The contraction shortens the muscle which moves the rigid structures, bones, to which they are attached.

Q.9. What kind of a skeleton does a snail have? Is it made of bones?

Ans -  The shell on the back of snails is called the exoskeleton or external skeleton. No, it is not made of bones.

Q.10 Why does an earthworm secrete a slimy substance?

Ans - An earthworm secrete a slimy substance because it helps them to move more easily through the soil.

Q.11. What are the wings of the birds made of?

Ans - Wings of birds are made up of feathers and hollow bones which help them to fly.

Q.12. How are joints important for our body?

Ans - Joints bind the skeleton together, to give structure and allow muscles to move bones to perform certain tasks such as running, reaching and holding.

Q.13. A muscle can only pull. How, then does it help in movement?

Ans - A single muscle can only pull, it cannot push. Thus, muscles work in pairs to move the bone. When one muscle contracts, it pulls the movable bone. When another muscle of the pair pulls, it brings the bone back to its original position.

Q.14. Why does a snake not move in a straight line?

Ans - Snakes move in S-shaped loops and in a zigzag manner. Each loop of the snake gives it a forward push by pressing against the ground.

Q.15. How does an earthworm make a grip on the ground?

Ans -  An earthworm has a large number of tiny bristles on the underside of its body that help it to grip the ground.

II. Give one term for each of the following:

(a) Structure formed by joining of chest bones with backbone. ribcage

(b) Shape of the fish which helps it to swim in water Streamlined body

(c) The framework of bones in our body Skeletal system

(d) The Manner of movement of an organism Gait

(e) Structure softer than the bone of which upper part of our ears is made. Cartilage

(f) Type of joint connection our neck to the head. Pivot joint

III. Fill in the blanks:

(a) The structure below the stomach which helps us to sit is pelvic bones.

(b) The joint between the upper jaw and the rest of the head is an example of fixed joint.

(c) Our muscles work in pairs.

(d) The bony part of the forelimbs of birds are modified as wings.

(e) Our forearm has two bones.

(f) A muscle can only pull, it cannot push.

IV. State whether True or False:

(a) A cockroach has four wings for flying. (True)

(b) Snails slither on the ground very slowly. (True)

(c) The body of an earthworm has the same structure as the body of a snake. (False)

(d) Fins help a fish to keep balance and direction while swimming. (True) 

(e) The shell of a snail is made of bones. (False)

(f) Our backbone is made of a single flexible bone. (False)

V. Match the following:

(a)  Upper part of ear -  (ii) Cartilage

(b) Forelimbs - (i) Wings

(c) Neck - (vi) Pivotal joint

(d) Shoulder - (iii) Ball and socket joint

(e) Upper jaw - (iv) Fixed joint

(f) Elbow - (v) Hinge joint

VI. Select the correct alternative:

(i) How many muscles are needed to move a bone?

Ans - (b) 2

(ii) A snail walks with the help of 

Ans - (c) Muscles

(iii) Which of the following have a backbone

Ans - (b) Snake

(iv) Which of these help(s) the fish to move?

Ans - (d) All of these

(v) The following figures show the models of some joints found in out body. Identify them.

Ans - (d) Ball and socket, hinge, pivotal

Class 6 Science-Workbook Chapter 7 Getting to know Plants

 Class VI

Chapter 7

Getting to know Plants

I. Answer the following questions in brief:

Q.1. What is petiole? Do all leaves have petioles?

Ans. The part of a leaf by which it is attached to the stem is called petiole. No all leaves do not have petioles. In some plants, leaves are attached directly to the plant stem.

Q.2. Where will you locate midrib in a leaf?

Ans. A midrib is commonly find at the back part of a leaf.

Q.3. If a plant has leaves with parallel venation what kind of roots will it have?

Ans. A plant has leaves with parallel venation will have fibrous roots.

Q.4. Name two climbers and two creepers.

Ans - Climbers : (a) Money Plant, (b) Green Peas

Creepers : (a) Pumpkin  (b) Water-Melon

Q.5. Which part of the plant helps it to stand upright?

Ans -The stem is the part of plant helps it to stand upright.

Q.6. What are lateral roots?

Ans -The smaller roots that grow on the main tap root are called lateral roots.

Q.7. Name the lowermost part of the pistil.

Ans - Ovary is the lowermost part of the pistil.

Q.8. Why are stems called 'two-way streets'?

Ans - Stems are called 'two-way streets' because water and minerals are transferred from the stem to the leaves in upward direction for photosynthesis at the same time food is transferred to other parts of the plant in downward direction.

Q.9. A potato has starch. Does it prepare starch itself? If not, where does this starch come from?

Ans - Potatoes do not make starch on their own. Starch is produced by the leaves and transported to the potatoes.

(H.w.) Q.10. Draw a diagram showing the inner structure of an ovary. Draw both longitudinal and transverse sections.

Ans -

II. Give one term for each of the following:

(a) The innermost part of flower  - Pistil

(b) Venation shown by leaves of plants heaving tap roots. Reticulate Venation

(c) Network of lines of a leaf. Veins

(d) Unwanted plants that grow themselves in a field. Weeds

(e) Plants that cannot stand upright and spread on the ground. -  Creepers

(f) Process of preparation of food by plants in the presence of sunlight. -  Photosynthesis 

III. Fill in the blanks:

(a) Roots anchor the plant to soil.

(b) Plants having fibrous roots have Parallel venation in them.

(c) Climbers take support of neighboring structures to stand upright.

(d) The topmost part of a stamen is called Anther.

(e) Stems transport water and minerals from roots to leaves though narrow tube(xylem) inside them.

(f) Water comes out of leaves in the form of vapour during the process of transpiration.

IV. State whether True or False

(a) Roots hold the plant upright. False

(b) Every flower has both stamens and pistil. False

(c) Number of petals in a flower is generally much more than the number of sepals. True

(d) All leaves have petioles in them. False

(e) Leaves make food which gets stored in potatoes in potato plants. True

(f) Carrot and radish that we eat are roots. True

(H.w.) V. Match the following:

Ans

VI. Select the correct alternative:

(i) Lateral roots are branches of

Ans (a) Tap roots

(ii) Which of the following parts of a plant in called a 'two-way street"?

Ans (d) Stem

(iii) Carrot, radish, turnip and tapioca are examples of 

Ans (b) Roots

(iv) Which of these is creeper?

Ans (b) Pumpkin

(v) Anther is a part of 

Ans (a) Stamen

(vi) Look at the Figures given below and state which of the following statements is true.

Ans (b) Leaves of plant in fig (a) have reticulate venation while those in fig (b) have parallel venation.

(H.w.) VII. Complete the following word puzzle with the help of the clues given below:

Class 8 Computer Chapter 2 Moving Ahead with HTML

 

Class VIII

 Chapter 2

Moving Ahead with HTML

 

A. Tick (ü) the correct answer and fill in the blank.

1. <B> tag displays text in bold.

2. ALIGN is not an attribute of FONT tag.

3.   /    symbol is used to indicate an end tag.

4. SIZE  attribute of <HR> is used to change thickness of line.

5.<H1>  is the largest heading element.

 

B. Write T for true or F for false.

1. HTML documents can be saved with .html or .htm extension only. True

2. <HR> is an example of non-empty tag. False

3. Attributes are always placed in the closing tag. False

4. BGCOLOR is an attribute of <FONT> tag. False

5. <LR> tag is used to add a line break in the web page. False

 

C. Fill in the blanks using the given words.

1. HTML is used to create Webpages.

2. attributes provides extra information to the browser about how to apply the tag.

3. Information enclosed in the TITLE tag is displayed in the title bar of the browser window.

4. BACKGROUND attribute of the BODY tag is used to set a picture in the background of web page.

5. <Hn> tag can display headings upto    6   levels.   

 

D. Answer in short.

Que 1.Which tag is used to change default font of the web page?

Ans -<FONT>tag is used to change default font of the web page.

Que 2. Which tag is used to make a text italics?

Ans -<I> tag is used to make a text italics.

Que 3.What should be the first tag in any HTML document?

Ans -<HTML>tag.

 

Que 4.What are the different types of Headings supported by HTML document?

Ans -To describe different levels of headings in the web page, <Hn> tag is used, where n is a number ranging from 1 to 6.

<H1> is the largest heading tag while <H6> is the smallest heading.

E. Answer in detail.

 

Que 1.Explain the use of BODY tag with its attributes.

Ans -<BODY>: This tag contains all the contents of the documents such as headings, paragraphs, images, hyperlinks, tables, lists, etc.

              It has following attributes:

 

BACKGROUND: Used to set a background image.

BGCOLOR: Used to set background color.

TEXT: Used to specify the text color.

 Format:

 

<BODY BGCOLOR=”blue” TEXT=”red”> …..</BODY>

<BODY BACKGROUND=”image_name” TEXT=”red”> …..</BODY>

 

Que 2.How can you change the font type, size and color of the text in HTML?

Ans -To change the font type use FACE attribute–

Format:<FONT FACE = “font name”>

Example:<FONT FACE = “Arial”>

 

To change the font size use SIZE attribute–

Format:<FONT SIZE = “value”>

Example:<FONT SIZE = “7”>

 

To change the font color use COLOR attribute–

Format:<FONT COLOR = “color name”>

Example:<FONT COLOR = “red”>

Que 3 What is the use of <MARQUEE> tag?

Ans –MARQUEE tag is used to add scrolling text on the web page. The DIRECTION attribute is used to choose the direction of scroll( up, down, left or right).

 Format: <MARQUEE DIRECTION = “position”> text….</MARQUEE>

               Where position = up, down, left, right.

 Example:

<MARQUEE> Welcome to our school</MARQUEE>

<MARQUEE DIRECTION= “up”> Class 8</MARQUEE>

<MARQUEE DIRECTION= “left”> Class 7</MARQUEE>

<MARQUEE DIRECTION= “down”> Class 6</MARQUEE>

<MARQUEE DIRECTION= “right”> Class 5</MARQUEE>

 

NCERT Class 6 Science - Workbook Chapter 6 Changes Around Us

Class VI

Science Workbook

Chapter 6 

Changes Around Us

I. Answer the following questions in brief:

Q.1 State whether the following changes can be reversed or not:

i) Blowing air into a balloon without bursting it. It can be reversed

ii) Baking a clay pot in the oven. It cannot be reversed

iii) Making a flower by paper cutting. It cannot be reversed

iv) Fixing a metal rim on a wooden wheel. It can be reversed

Q.2. Can we bring about a change in a substance without heating it? If so, how?

Ans. Yes we can bring about a change in a substance without heating it. By mixing a different substance on it.

Q.3. A potter shapes a lump of clay into a pot on his wheels and then takes it into an oven. Point out the changes that can be reversed or cannot be reversed in this process.

Ans. Potter shapes a lump of clay into a pot it is reversible change or physical change. When it takes into an oven it is irreversible change or chemical change.

Q.4. Why are metal rims heated to fix them onto the wooden wheels? Can this change be reversed?

Ans. The metal rim is made slightly smaller than the wooden wheel. On heating, the rim expands and fits onto the wheel. Cold water is then poured over the rim, which contracts and fits tightly onto the wheel. Yes this change be reversed.

Q.5. Melting of wax is a reversible change while burning of candle is non-reversible. Justify this statement.

Ans. The melting of the wax is a reversible change as the shape of the wax can be obtained by heating it. While the burning of candle is an irreversible change as the burnt candle thread cannot be obtained.

II. Give one term for each of the following:

a) Changing a solid into liquid by heating. Melting

b) Changing of water vapour into liquid by cooling. Condensation

c) Reduction in size of a substance due to cooling. Contraction

d) Increase in size of a substance due to heating. Expansion

e) Change of liquid water into gas form. Evaporation

III. Fill in the blanks:

a) A change may occur by mixing a substance with some other.

b) We can change a substance by heating it.

c) A change may occur by heating a substance.

d) Some changes can be reversed while others cannot be done so.

e) A substance contracts when it is cooled.

IV. Write whether True or False 

a) The metal ring in tools is made slightly larger than the handle. (False)

b) Separating bran from wheat flour is a change that can be reversed. (False)

c) Stretching a rubber is a change that can be reversed. (True )

d) The size of the metal rim to be fixed on a wooden wheel is slightly smaller than it. (True)

e) On blowing air into a balloon, it bursts. It is a change that can be reversed. (False)

V. Match the following:

Ans.

a) Drying clothes usder the sun - (vi) Evaporation

b) Change of water vapour into liquid - (v) Condensation

c) Reduction in size by cooling - (iii) Contraction

d) Change of liquid water into gas form - (ii) can be reversed

e) Increase in size by heating - (i) Expansion

d) Sprouting of seeds - (iv) can't be reversed

VI. Select the correct alternative:

(i) The metallic rim which is to be fitted onto a wooden wheel should be

Ans - a) slightly smaller that the wheel

(ii) We can bring about a change in a substance by 

Ans - c) Both of these

(iii) Water and sugar are added to obtain sugar solution. We can get the original substances by

Ans - d) Evaporation and Condensation

(iv) Shown below are some activities to bring about changes in substances.

The changes that can be reversed from among these are

Ans - d) IV and I

(H.W.) 

VII. Complete the following word puzzle using the clues given below:

Class 7 Chapter 4 Let's Learn HTML

Class VII

CHAPTER 4

Let’s Learn HTML

 

A. Tick (ü) the correct answer and fill in the blank.

1. Notepad is an example of Text editor.

2. Every HTML document consists of tags.

3. The tags are always enclosed within pair of angular brackets.

4. <BR> is an example of Empty tag.

5.   .htm   is the extension of HTML document.

 

B. Fill in the blanks using the given words.

 

1. HTML is used to create web pages.

2. Attribute provides extra information to the browser about how to apply the tag.

3. Information enclosed in the title tag is displayed in the title bar of the browser window.

4. BACKGROUND attribute of the BODY tag is used to set a picture in the background of web page.

 

C. Encircle the errors in the following statements. Rewrite them correctly.

D. Answer in short.

 

Que 1 What are tags in HTML?

Ans - HTML tags are the special keywords enclosed between the angle brackets (< and >) that convey a meaning to the web browser about how to display the contents followed by them.

 

Que 2 Name the two types of HTML tags?

Ans – The two types of HTML tags are:

 

*      Non empty tag (or Container tag)

        Example–  HTML tag, Body tag, Head tag, TITLE tag.

 

*      Empty tag (or Non Container tag)

        Example–  Line Break tag.

 

 

Que 3 What are the two kinds of editors?

Ans – The two types of editors are:

*      WYSIWYG editors

        Example – Front Page and Adobe Dreamweaver.

 

*      Text editors

            Example – Notepad and Word Pad.

 

Que 4 What is the default color of an HTML document?

Ans - White Colour.

 

Que 5 Name the tag that contains all the contents of the web page.

Ans – Body tag       .

 

E. Answer in detail.

Que 1 Differentiate between empty and non empty tags.

Ans – Non-Empty Tag- These type of tags have a starting as well as an ending tag and are called container tags or non-empty tags. For example -     <HTML>…</HTML>, <BODY>…</BODY> tags.

                 Empty Tag- There are some tags which do not need the ending tag.  For example, <HR>, <BR> tags.

 

Que 2 How are HTML documents viewed in web browsers?

Ans – The saved HTML document can be viewed in a web browser like Google Chrome, Mozilla Firefox, Opera, etc.

Open the folder where you have saved the HTML document and double-click on the HTML document.

The HTML document will open as a web page in the web browser window.

 

Que 3 Explain the use of Body tag.

Ans - The Body tag appears after the Head tag. All the contents of the web page, i.e. text, graphics, links, images, etc. are enclosed in between the Body tag.

 

Que 4. Write some features of HTML?

Ans – The features of HTML are:

*      HTML documents are simple text files.

*      There is no need of compilation of HTML codes.

*      HTML is not a case sensitive language.

*      HTML documents can be written in any text editor like Notepad or WordPad.

*      HTML documents can be viewed in any browser and in type of operating system.