CBSE Class 7

In this page, we are providing Fibre to Fabric Class 7 Extra Questions and Answers Science Chapter 3 pdf download. NCERT Extra Questions for Class 7 Science Chapter 3 Fibre to Fabric with Answers will help to score more marks in your CBSE Board Exams.

Class 7 Science Chapter 3 Extra Questions and Answers Fibre to Fabric

Extra Questions for Class 7 Science Chapter 3 Fibre to Fabric with Answers Solutions

Fibre to Fabric Class 7 Extra Questions Very Short Answer Type

Question 1.
Of which nutrient silk fibre is made?
Answer:
Protein

Question 2.
What are silkworms?
Answer:
Silkworm are caterpillars of silk moth.

Question 3.
What are larvae called?
Answer:
Caterpillars or silkworms

Question 4.
What is the process of taking out silk threads from the cocoon called?
Answer:
Reeling the silk

Question 5.
Where is reeling done?
Answer:
In special machines

Question 6.
What spins the cocoons inside which develops the silk moth?
Answer:
Caterpillar or silkworm

Question 7.
How many eggs do a female silk moth lay at a time?
Answer:
Hundreds of eggs.

Question 8.
Where are the eggs stored?
Answer:
The eggs are stored on strips of cloth or paper

Question 9.
Why are moths reared?
Answer:
Moth are reared for obtaining silk.

Question 10.
Why are cocoons collected?
Answer:
Cocoons are collected to get silk threads.

Question 11.
Where are larvae kept in the process of rearing?
Answer:
Larvae are kept in clean bamboo trays.

Question 12.
In which country silk industry begun?
Answer:
China

Question 13.
What is silk route?
Answer:
The route, the traders and travellers travelled to introduce silk to other countries is called silk route.

Question 14.
Which country leads the world in silk production?
Answer:
China

Question 15.
Name two varieties of silk.
Answer:
Tassar silk and mooga silk

Question 16.
What is the nature of silk fibre obtained from the cocoon of mulberry silk moth?
Answer:
It is soft, lustrous and elastic.

Question 17.
What is pupa?
Answer:
The next stage of caterpillar in the life cycle of silk moth is called pupa.

Question 18.
What is sericulture?
Answer:
The rearing of silkworms for obtaining silk is called sericulture.

Question 19.
What is cocoon?
Answer:
The silky covering spun by the larvae of silkmoth for protection as pupae is called cocoon.

Question 20.
Name two wool yielding animals.
Answer:
Yak, sheep.

Question 21.
Name two finished products of wool.
Answer:
Sweater, shawl.

Question 22.
Name two types of fibres of the hairy skin of the sheep.
Answer:
The coarse beard hair and the fine soft under-hair close to the skin.

Question 23.
What are occupational hazards?
Answer:
Risks faced by the workers in any industry are called occupational hazards.

Fibre to Fabric Class 7 Extra Questions Short Answer Type

Question 1.
What keeps the wool yielding animals warm?
Answer:
The wool yielding animals like sheep, goat, yak, etc., have a thick hair on their body. Hair trap a lot of air. Air is a poor conductor of heat, which does not allow the heat absorbed to release from their body and keeps them warm.

Question 2.
Explain selective breeding.
Answer:
In some animals, to get desired characters in offsprings parents are selected having that desired characters for breeding. This process is known as selective breeding. For example, some breed of sheep are selected for their soft under-hair.

Question 3.
There are other sources of wool except sheep. Explain.
or
Mention other sources of wool than sheep.
Answer:
The fleece of sheep is not the only source of wool. There are some other sources for obtaining wool. Such as yak wool is common in Tibet and Ladakh. Angora wool is obtained from angora goats found in hilly regions. Wool is also obtained from camel hair. Llama and Alpaca found in South America also yield wool.

Question 4.
Explain rearing and breeding of sheep.
Answer:
Sheep are reared in many parts of the country for obtaining wool. Sheep are herbivores and so they feed on grass and leaves and other products like pulses, corn, jowar, oil cakes, etc. In winter season, they are kept indoors and feed on leaves, grain and dry fodder. Some sheep are ‘selectively bred, with one parent being a sheep of good breed for obtaining specific characteristics in their off spring.

Question 5.
What is shearing? Explain.
Answer:
Once the reared sheep have developed a thick growth of hair, it is shaved off for getting wool. The process of removing the fleece (hair) of the sheep along with a thin layer of skin from its body is called shearing. It does not hurt the sheep.

Question 6.
What is scouring? Explain.
Answer:
In the process of making wool from fibres, scouring is done after shearing. The sheared skin with hair is thoroughly washed in tanks to remove grease, dust and dirt. This is called scouring. Nowadays, it is done by machines.

Question 7.
Define sericulture.
Answer:
Silk fibres are animal fibres obtained from cocoons of the silkworm. The rearing of silkworms for obtaining silk is called sericulture. It is a very old occupation in India.

Question 8.
What is called reeling the silk?
Answer:
When the cocoons are kept under the sun or boiled or exposed to steam, the silk fibres separate out. The process of taking out threads from the cocoons for use as silk is called reeling the silk. It is done in special machines, which unwind the thread or fibres of silk from the cocoon.

Question 9.
How are the silkworms reared?
Answer:

Silk moths are reared and their cocoons are collected to get silk threads. The eggs laid by a female silk moth are stored carefully on strips of cloth or paper and sold to silkworm farmers. The farmers keep eggs under hygienic and suitable conditions of temperature and humidity.

Fibre to Fabric Class 7 Extra Questions Long Answer Type

Question 1.
Describe in brief about the animals that yield wool.
Answer:
The animals that yield wool are sheep, yak, goat, camel, etc. The wool commonly available in the market is sheep wool. Yak wool is common in Tibet and Ladakh. Angora goats yield angora wool, which are found in hilly areas such as Jammu and Kashmir.

The under fur of Kashmiri goat is soft and so it is woven into fine shawls called Pashmina shawls. The hair on the body of camels is also used as wool. Llama and Alpaca also yield wool. They are found in South America. Wool obtained from different animals and based on their quality are used to make different kinds of woollen things.

Question 2.
What are the various steps for processing fibres into wool?
Answer:
The processing of fibres into wool involves various steps such as shearing, scouring sorting, dyeing and rolling. They have been discussed below in brief:

Step 1. Shearing: First of all, the woollen coat or fleece from the animals along with a thin layer of skin is removed from their body. The process is called shearing.
Step 2. Scouring: The sheared skin with hair is thoroughly washed in tanks to remove grease, dust and dirt from the wool. This is called scouring.
Step 3. Sorting: It is done after scouring. The hairy skin is sent to a factory where hair of different textures are separated or sorted.
Step 4. The small fluffy fibres called burrs, are picked out from the hair. The fibres are scoured again and dried. Now the wool is ready to be drawn into fibres.
Step 5. The fibres are dyed in various colours because the natural fleece of sheep and goats is black, brown or white.
Step 6. Finally the fibres are straightened, combed and rolled into yarn. The longer fibres are made into wool for sweaters and the shorter ones are spun and woven into the woollen cloth.

Question 3.
Describe the life history of a silk moth with the help of figures of each stage.
Answer:
Silk fibres are also known as animal fibres. They are soft, light in weight and strong. Silk fibres are obtained from the cocoons of the silk moth or silkworm. The life history of silk moth involves mainly four stages:

Eggs ➝ Caterpillars or Silkworms ➝ Pupa ➝ Adult silk moth

The female silk moth lays eggs, from which hatch larvae called caterpillars or silkworms. They grow in size and when they are ready to enter the next stage called pupa, they first weave a net to hold themselves. Then they swing their heads from side to side in the form of the figure 8.

During these movements, they secret fibres made of a protein which hardens on exposure to air and becomes silk fibre. Soon the caterpillars completely cover themselves by silk fibres and turn into pupae. This covering is known as cocoon. The further development of the pupae into moths continue inside the cocoons. Moths are reared and their cocoons are collected to get silk thread for obtaining silk.

Question 4.
Describe how silkworms are reared and silk is processed.
or
Mention the process of getting silk from cocoon.
Answer:
Silk moths are reared and then cocoons are collected to get silk threads for obtaining silk. A female silk moth lays hundreds of eggs which are stored carefully on strips of cloth or paper and sold to farmers. The farmers keep the eggs under hygienic conditions and under suitable conditions of temperature and humidity.

The eggs are warmed at certain temperature for the larvae to hatch from eggs. This is done when mulberry trees bear a fresh crop of leaves. The larvae called caterpillars or silkworms, eat up these leaves and grow rapidly and increase enormously in size. The larvae are kept in clean bamboo trays along with freshly chopped mulberry leaves.

After 25 to 30 days, the caterpillars stop eating and move to a small chamber in the tray to spin cocoons. The caterpillars or silkworms spin the cocoons inside which develops the silk moth. The cocoons are kept under the sun or boiled or exposed to steam. The silk fibres separate out. Silk fibres are then spun into silk threads, which are finally woven into silk cloth by weavers.

Fibre to Fabric Class 7 Extra Questions HOTS

Question 1.
Why is silk obtained by mulberry silk moth most popular?
Answer:
Silk obtained by mulberry silk moth is most popular because of its shimmering appearance which produces different colours.

Question 2.
You have been asked to buy a woollen sweater from the market. How will you check its purity.
Answer:
We can test the purity of the woollen sweater by burning it. Take about 10 cm long thread (spare one). Hold it with the help of a tong and burn its one end. If the fibre smells like burning hair, it is wool but if . the fibre smells like chemicals or burning plastic, it is artificial wool.

On blowing out of the flame touch the end of the fibre. If the end turn to dust on touching then it is pure wool but if the end has melted and turned hard, then it is not pure wool.

Question 3.
Why natural fibres are costlier than synthetic fibres?
Answer:
Natural fibres are obtained either from plants or animals. The process of obtaining fibres from these natural sources is comparatively labour intensive process than production of synthetic fibres on large scale from other raw materials or chemicals.

Question 4.
Compare the properties of silk and wool.

Question 5.
What are occupational hazards? What occupational hazards are linked with wool and silk production?
Answer:
Health risks faced by the workers of a particular occupation or industry are called occupational hazards. In wool industry, wool sorter’s can get infected by a bacterium which causes fatal blood disease, called anthrax or sorter’s disease. In silk industry workers handling dead worms with bare hands may get infection. Fine hair on caterpillars may cause asthma or conjunctivitis.

Fibre to Fabric Class 7 Extra Questions Value Based (VBQs)

Question 1.
Sania got upset on learning that for obtaining 1 kg of raw silk around 5,000 cocoons are killed. But her mother explained her that silkworms are also conserved in this process for obtaining silk next time. Also it is the source of income to many rural and needy person.
(a) Why silk are famous?
(b) Whom do you agree- Sania or her mother? Why?
(c) If you get an option to select between a silk dress and a dress made of synthetic fibre which one will you select and why?
(d) What value of Sania is shown here?

Answer:
(a) Silk are famous for its smooth and lustrous fibre which is also strong.
(b) Do it yourself.
(c) Hint: While selecting dress one should always keep in mind the advantages and disadvantages of natural and synthetic fibres.
(d) Sania is eco-friendly, sensitive and concern for other creatures.

Question 2.
Many occupational hazards are associated with wool and silk production. Most of these hazards can be prevented by just having a proper awareness and knowledge of how to tackle such conditions. The main reason for occupational hazards in India is due to poverty, illiteracy and poor hygienic conditions.
(a) What occupational hazards are associated with wool and silk industries?
(b) How can most of the occupational hazards be minimised?
(c) What values of people are shown here?

Answer:
(a) 1. Wool industry: Anthrax or sorter’s disease
2. Silk industry: Infections, asthama and conjunctivitis

(b) Occupational hazards can be minimised by
1. taking precaution while handling animals like wearing gloves, mask, using disinfectants, washing hands, etc.
2. having proper knowledge and awareness of signs and symptoms of diseases of human and animal.

(c) People are ignorant, careless and illiterate.

In this page, we are providing Nutrition in Animals Class 6 Extra Questions and Answers Science Chapter 2 pdf download. NCERT Extra Questions for Class 6 Science Chapter 2 Nutrition in Animals with Answers will help to score more marks in your CBSE Board Exams.

Class 7 Science Chapter 2 Extra Questions and Answers Nutrition in Animals

Extra Questions for Class 7 Science Chapter 2 Nutrition in Animals with Answers Solutions

Nutrition in Animals Class 7 Extra Questions Very Short Answer Type

Question 1.
Do all animals have the same mode of nutrition?
Answer:
No

Question 2.
Name the mode of nutrition in which solid whole food particles is ingested.
Answer:
Holozoic

Question 3.
Name the chambers in the stomach of a ruminant.
Answer:
Rumen, reticulum, omasum and abomasum

Question 4.
Name the organ which identifies the taste of different food materials.
Answer:
Tongue

Question 5.
What is the other name of foodpipe?
Answer:
Oesophagus

Question 6.
Name the hard outer surface layer of your teeth.
Answer:
Enamel

Question 7.
Name some parasites of human body.
Answer:
Tapeworm and roundworm

Question 8.
What is the other name of digestive tract?
Answer:
Alimentary canal

Question 9.
Which is the largest gland of the human body?
Answer:
Liver

Question 10.
What are taste buds?
Answer:
Taste buds are the receptor cells which helps us in recognising taste of the food.

Question 11.
Apart from tasting food what are the other functions of tongue?
Answer:
Helps in chewing food and speaking.

Question 12.
What is the function of oesophagus?
Answer:
The wall of oesophagus pushes the food down to the stomach.

Question 13.
State the functions of molar and premolar teeth.
Answer:
The functions of molar and premolar teeth are to chew and grind the ingested food.

Question 14.
What is mastication?
Answer:
Mastication or chewing is the process of crushing and grinding of food by teeth.

Question 15.
Name the various types of teeth.
Answer:

1. Incisors
2. Canines
3. Premolars
4. Molars

Question 16.
What are milk teeth?
Answer:
The set of teeth that grows during infancy are called milk teeth. They fall off at the age of 6-8 years.

Question 17.
What is peristalsis?
Answer:
A series of contraction and relaxation in alimentary canal which helps in movement of food is called peristalsis.

Question 18.
Define nutrition.
Answer:
The process of intake of food and its utilisation by an organism is known as nutrition.

Question 19.
What is assimilation?
Answer:
Assimilation is the process by which the absorbed food is utilised to build up complex substances (like protein and fat) and to give energy.

Question 20.
Define absorption.
Answer:
The digested food gets absorbed by the inner walls of small intestine and passes into the blood vessels. This process is known as absorption.

Question 21.
Why is digestion of fats difficult as compared to that of other nutrients?
Answer:
Fats cannot be digested easily because they are insoluble in water and are present as large globules.

Question 22.
Does bile juice digest fat completely?
Answer:
No. Bile juice only breaks down big fat droplets into smaller droplets which can be easily digested by the enzymes released from the pancreas.

Nutrition in Animals Class 7 Extra Questions Short Answer Type

Question 1.
Write about pseudopodia.
Answer:
The finger-like projections in Amoeba are called pseudopodia. These projections are not permanent. They are formed out of the body of Amoeba, whenever they are needed. Pseudopodia helps in movement and capturing food.

Question 2.
Name some of the components of food.
Answer:
Some of the important components of food are:

1. carbohydrates
2. proteins
3. minerals
4. fats
5. vitamins
6. water and roughage

Question 3.
What is animal nutrition?
Answer:
Animal nutrition includes nutrient requirement, mode of intake of food and its utilisation in the body for growth, repair and its functioning.

Question 4.
Write the names of various digestive organs of the body.
Answer:

1. buccal cavity
2. oesophagus
3. stomach
4. small intestine
5. large intestine
6. rectum
7. anus

Question 5.
Explain the mode of feeding of starfish.
Answer:
Starfish feeds on the animals covered with hard shells of calcium carbonate. After opening the shell, starfish pops out its stomach and eats the soft animal present inside the shell. Then the stomach goes back into the body and the food slowly gets digested.

Question 6.
Explain the process of digestion in stomach.
Answer:
Partial digestion of food takes place here. Stomach releases gastric juice, which mainly contains hydrochloric acid and pepsin. Hydrochloric acid kills germ entering with the food and makes the food acidic. Pepsin helps in digestion of protein. Churning of stomach muscles physically breaks down food and mix it with the gastric juice and convert it into a semi-fluid called chyme.

Question 7.
Write the functions of different types of teeth in human beings.
Answer:

1. Incisors: They help in cutting and biting food.
2. Canines: They help in piercing and tearing food.
3. Premolars: They help in chewing and grinding food.
4. Molars: They also help in chewing and grinding food.

Question 8.
Explain rumination.
Answer:
The grass-eating animals quickly swallow the grass while eating which gets stored in a separate part of their stomach called ‘rumen’. Here, the food gets digested partially and is called ‘cud’. Later, this cud again returns to the mouth in small lumps and the animal chews it properly. This process is called ‘rumination’.

Question 9.
Define tongue. What are its functions?
Answer:
The fleshy muscular organ attached at back to the floor of the buccal cavity is called tongue. It is free at front and can move in all directions.
The functions of tongue are:

• It mixes saliva with food.
• It helps in swallowing the food.
• It helps in identifying the various tastes of different food materials, as it has various taste buds which help in detecting them.

Question 10.
Write about Amoeba.
Answer:
Amoeba is a small microscopic, single-celled organism found in pond water. It has a cell membrane, a dense and round nucleus, and many small bubble-like vacuoles in its cytoplasm. Amoeba can change its shape and position constantly.

Question 11.
Explain digestion of food in mouth.
Answer:
Food enters the buccal cavity through mouth. Here it is chewed by teeth, and gets mixed with saliva with the help of tongue. Saliva contains an enzyme called ptyalin (salivary amylase). This enzyme converts complex carbohydrates like starch into sugars. Saliva moistens the food and changes it into a round bolus.

Question 12.
Write about pancreas.
Answer:
Pancreas is a large cream-coloured gland, which is located just below the stomach. It secretes pancreatic juice into the small intestine which acts on carbohydrates, fats and proteins and changes them into simpler forms.

Question 13.
Why the large intestine is shorter and wider than small intestine?
Answer:
In large intestine only absorption of water takes place from the undigested food so it is shorter and wider. In small intestine, digestion takes place therefore more surface area is needed for nutrient absorption. Hence, small intestine is narrower and longer.

Question 14.
Write about large intestine.
Answer:
Large intestine begins with the caecum and ends with the rectum. It includes the caecum and the colon and the rectum. It extracts moisture from food residues which are later excreted as faeces. It is wider and shorter than small intestine; so its length is about 1.5 metre.

Nutrition in Animals Class 7 Extra Questions Long Answer Type

Question 1.
Define dental plaque. What harm can it cause? How can the formation of plaque be prevented?
Answer:
If teeth are not cleaned regularly and properly they get covered with a sticky, yellowish layer of food particles and bacteria. This is called ‘dental plaque’.

Because plaque entirely covers the teeth by its layer, the alkaline saliva cannot reach their surface to neutralise the acid formed by bacteria. Hence, tooth decay is caused. Tooth decay can be prevented by brushing and cleaning the teeth as well as mouth properly and regularly.

Question 2.
What is diarrhoea? How is it caused? How can it be prevented?
Answer:
Diarrhoea is the frequent and watery bowel movement. It could be caused by infection or food poisoning or indigestion. It can be fatal under severe conditions. This disease causes excessive loss of water and salts from the body.

It can be prevented by taking plenty of boiled and cooled water, along with a pinch of salt and sugar dissolved in it. This is called Oral Rehydration Solution (ORS).

Question 3.
Explain feeding and digestion in Amoeba with a labelled diagram.
Answer:
Amoeba feeds on microscopic organisms. When it senses food, it pushes out pseudopodia around the food particle and engulfs it. The food becomes trapped in a food vacuole. Digestive juices are secreted into the food vacuole which act on the food and break down it into simpler substances. Digested food is absorbed into the cell and undigested food is expelled outside by the vacuole.

Question 4.
Explain the process of nutrition in human beings from ingestion to egestion.
Answer:
(i) Ingestion: It is the process of taking food into the mouth; i.e., starting point of the alimentary canal.
(ii) Digestion: Digestion is the process of breaking of ingested food into simpler substances. Digestion occurs through two processes, i.e., mechanical (chewing, grinding, mixing, churning) and chemical (enzymes, bile, acid). Mechanical processes helps in breaking the large food particles into smaller ones and mixing them well with the chemicals secreted by alimentary canal.

Digestion of starch starts at mouth with the action of salivary amylase. Digestion of protein starts in stomach with the help of enzyme pepsin and digestion of all the three components of food, viz., carbohydrate, protein and fat is completed in the small intestine.
(iii) Absorption: Digested food is absorbed into the blood through finger-like structures, called villi, present in the small intestine.
(iv) Assimilation: It is the process where absorbed substances are transported to different organs of the body via blood vessels to build complex substances like protein, enzyme, etc.
(v) Egestion: The process of elimination of undigested food through anus is called egestion.

Question 5.
Explain human digestive system with a labelled diagram.
Answer:

The digestive system in humans consists of an alimentary canal and digestive glands which help in
digestion. Different parts of alimentary canal are:

1. Mouth: Digestion begins in mouth. Teeth cuts the food into small bits. Saliva digest starch in food and softens the food to pulp. Tongue helps to mix the food with saliva and converting food into bolus.
2. Oesophagus: Wall of oesophagus contracts and transports food from mouth to stomach.
3. Stomach: It is a big muscular bag which secretes digestive juice. Hydrochloric acid in digestive juice kill germs and enzyme pepsin breaks protein to amino acids. In stomach food get converted into a semi-fluid, chyme.
4. Small intestine: Secretions from liver and pancreas act on the food in small intestine. Bile helps in breaking large fat molecules into tiny droplets. Pancreatic juice helps in digestion of starch and protein. Intestinal juice acts on starch, protein and fat and completes the digestion. Villi in small intestine absorbs these digested nutrients into the blood vessels.
5. Large intestine: Large intestine absorbs water and some useful nutrients from the undigested food. The undigested food is then eliminated as faeces from the anus.

Question 6.
Write a short note on nutrition in ruminants.
Answer:

1. grass-eating animals swallow the food quickly and store it in the rumen. Rumen inhabits cellulose digesting bacteria.
2. The partially digested food then goes to next chamber of the stomach the reticulum.
3. Digestive juices of the reticulum turns food into cud.
4. While resting, cow brings back the cud into mouth for regurgitation.
5. Food is chewed completely and swallowed into omasum for further digestion.
6. Then the food moves into abomasum for digestion brought about by digestive juices.
7. A large sac-like structure called the caecum lies between the small and large intestines.
8. The symbiotic bacteria present in the caecum help incomplete digestion of cellulose. Digestion of food is completed in the small intestine.

Question 7.
Solve the crossword given below:

Answer:

Across:
1. Cream-coloured digestive gland
4. Organ that mixes saliva with the food
5. Point of defaecation
7. Stored in gall bladder
10. Finger-like outgrowth in the small intestine
13. Kind of taste buds
14. Kills bacteria in the stomach

Down:
2. Feeds with the help of pseudopodia
3. Undigested excretory solid residues
6. Total number of molars in one jaw of an adult
8. Largest gland
9. Watery secretion in the mouth
11. A ruminant
12. Form of food chewed by ruminants
Answer:

Nutrition in Animals Class 7 Extra Questions HOTS

Question 1.
Can you tell which kind of food items are not digested easily when gall bladder of a person is removed surgically? Why?
Answer:
Food items rich in fats cannot be digested easily when gall bladder of a person is removed. Gall bladder stores bile juice in concentrated form which is secreted in small intestine when needed. Bile juice breaks the larger molecules of fats into smaller one.

Question 2.
Name the part of alimentary canal where

1. water gets absorbed from undigested food.
2. digested food gets absorbed.
3. bile juice is produced.
4. taste of the food is perceived.
5. germs get killed.
6. undigested food is removed.
7. food is converted into bolus.
8. food is converted into chyme.

Answer:

1. Large intestine
2. Small intestine
3. Gall bladder
4. Tongue
5. Stomach
6. Anus
7. Mouth
8. Stomach

Question 3.
What is the role of fibrous food in bowel movement?
Answer:
Fibrous food increases the stool bulk, so it ease the bowel movement and reduce constipation.

Question 4.
How food moves in the opposite direction during vomiting?
Answer:
When food is not accepted by our stomach, then the wall of the alimentary canal pushes back the food in upward direction and it is vomited out.

Question 5.
Why it is advised not to eat hurriedly and talk or laugh while eating.
Answer:
This is because inside the throat, air and food share a common passage. When we talk flap-like valve of wind pipe opens and when we eat or swallow food it remains close. When we eat hurriedly and talk or laugh while eating, the valve of windpipe get open or does not close properly. If, by chance food particles enter the windpipe, we feel choking or get hiccups.

Nutrition in Animals Class 7 Extra Questions Value Based (VBQs)

Question 1.
In a birthday party, Ram filled his plate with oily and sugary food. His elder sister Sarita on seeing this interrupted him. She told him that it is not good to eat too much of this kind of food. She asked him to share that plate with his friends and suggested to include some vegetables and salads also.
(a) Why eating oily and sugary food not good for health?
(b) What is the effect of sugary food on our teeth? How we can prevent it?
(c) Where do sugary food get digested in alimentary canal?
(d) What value of Sarita is shown here?

Answer:
(a) Too much sugary food and oily foods are not good for health as it causes secretion of much acid from stomach and thus causes indigestion. Sugary foods causes tooth decay, makes our stomach feel full and in long term obesity. Oily food also cause obesity and thus many health problems.
(b) Sugary food sticking to our teeth facilitates growth of harmful bacteria which break down the sugars into acids. This acid gradually damage the teeth causing tooth decay. We can prevent tooth decay by brushing our teeth at least twice a day and rinse the mouth after every meal. We must also avoid too much chocolates, sweets or sugar products as they are the major cause of tooth decay.
(c) Sugary food gets digested in small intestine.
(d) Sarita is intelligent, understanding and knows value of food so instead of throwing oily and sugary food she asked Ram to share it with his friends.

We are providing students with chapter-wise CBSE class 7 Science notes. These Class 7 Science Notes are put together by subject experts and based on the latest CBSE syllabus. The free NCERT Class 7 Science Notes PDF available here come with detailed explanations of important topics to further make learning easy for students.

CBSE Class 7 Science Notes

Below shows the CBSE Class 7 Science Notes for all the chapters. Students can check out these notes by clicking on the link below.

1. Nutrition in Plants Class 7 Notes
2. Nutrition in Animals Class 7 Notes
3. Fibre to Fabric Class 7 Notes
4. Heat Class 7 Notes
5. Acids, Bases and Salts Class 7 Notes
6. Physical and Chemical Changes Class 7 Notes
7. Weather, Climate and Adaptations of Animals to Climate Class 7 Notes
8. Winds, Storms and Cyclones Class 7 Notes
9. Soil Class 7 Notes
10. Respiration in Organisms Class 7 Notes
11. Transportation in Animals and Plants Class 7 Notes
12. Reproduction in Plants Class 7 Notes
13. Motion and Time Class 7 Notes
14. Electric Current and Its Effects Class 7 Notes
15. Light Class 7 Notes
16. Water: A Precious Resource Class 7 Notes
17. Forests: Our Lifeline Class 7 Notes
18. Wastewater Story Class 7 Notes

In this page, we are providing Nutrition in Plants Class 7 Extra Questions and Answers Science Chapter 1 pdf download. NCERT Extra Questions for Class 7 Science Chapter 1 Nutrition in Plants with Answers will help to score more marks in your CBSE Board Exams.

Class 7 Science Chapter 1 Extra Questions and Answers Nutrition in Plants

Extra Questions for Class 7 Science Chapter 1 Nutrition in Plants with Answers Solutions

Extra Questions for Class 7 Science Chapter 1 Very Short Answer Type

Question 1.
Name the components of food.
Answer:
Carbohydrates, fats, proteins, vitamins, and minerals.

Question 2.
What are stomata?
Answer:
Tiny pores on the leaves are known as stomata.

Question 3.
Name the pigment which makes leaves green.
Answer:
Chlorophyll

Question 4.
State the function of chlorophyll.
Answer:
It captures energy of sunlight.

Question 5.
Name the unit which makes the bodies of living organisms.
Answer:
Cell

Question 6.
Give an example of an insectivorous plant.
Answer:
Sundew plant

Question 7.
What is the mode of nutrition of Cuscuta?
Answer:
Parasitic

Question 8.
What are the main parts of a cell?
Answer:

• Cell membrane
• Nucleus
• Cytoplasm

Question 9.
Which mode of nutrition is used by green plants?
Answer:
Autotrophic mode

Question 10.
Why insectivorous plants feed on insects?
Answer:
Insectivorous plants feed on insects to fulfill their nitrogen needs.

Question 11.
What are the raw materials for photosynthesis?
Answer:

• Water
• CO₂
• Sunlight
• Chlorophyll

Question 12.
What is autotrophic nutrition?
Answer:
The type of nutrition in which organism prepare their own food is known as autotrophic nutrition.

Question 13.
What is photos3mthesis?
Answer:
The process by which green plants prepare their own food using CO₂ and water in the presence of sunlight and chlorophyll is called photosynthesis.

Question 14.
What are heterotrophs?
Answer:
The type of organisms which depend on other organisms for their food are known as heterotrophs.

Question 15.
What do you mean by saprophytic nutrition?
Answer:
The type of nutrition in which organisms depend upon dead and decaying matter for their food is known as saprophytic nutrition.

Question 16.
Name two plants that have a symbiotic relationship with Rhizobium bacteria.
Answer:
Peas and moong

Question 17.
What are insectivorous plants? Give an example.
Answer:
The plants which trap insects for feeding are called insectivorous plants. For example, pitcher plant.

Question 18.
What are parasites?
Answer:
The organisms which obtain nutrients from other organisms are called parasites.

Question 19.
What is host?
Answer:
The organisms which provide nutrients to another organism, known as parasites, is called host.

Extra Questions for Class 7 Science Chapter 1 Short Answer Type

Question 1.
What is haustoria?
Answer:
Haustoria is the root of a parasitic plant that penetrates the host’s tissue and draws nutrients from it.

Question 2.
Differentiate between parasitism and symbiosis.
Answer:
Parasitism

• It is a relationship between two organisms which is beneficial to one and harmful to the other.
• One of the partner which draws food is called parasite and the other which provide nutrients is called host.
• Example: Cuscuta

Symbiosis:

• It is a relationship in which two organisms live together in a manner benefited.
• Each partner of the relationship is called a symbiont.
• Example: Lichen

Question 3.
List some harmful effect of fungi.
Answer:

• They cause diseases in crops, animals and humans.
• They spoil fruits, vegetables and all kinds of foodstuff.
• They spoil leather items and clothes.

Question 4.
How does a pitcher plant trap insects?
Answer:
The leaf of pitcher plant is modified into a pitcher-like structure. The apex of the leaf forms a lid over it which can open and close. Inside the pitcher, there are hair which are directed downwards. When an insect lands in the pitcher, the lid closes and the insect get trapped into the hair and then insect is digested by the digestive juice secreted by the pitcher.

Question 5.
From where do the plants obtain nitrogen?
Answer:
Soil has certain bacteria that convert gaseous nitrogen into a usable form and release it into the soil. These soluble forms are absorbed by the plants along with water. Plants also obtain nitrogen from the fertilizers added by the farmers.

Question 6.
Explain the symbiotic relationship in lichens.
Answer:
In lichens, a chlorophyll-containing partner, an alga, live together with a fungus. The fungus provides shelter, water, and minerals to the alga and in return, the alga provides food which it prepares by photosynthesis.

Question 7.
Explain the symbiotic relationship between Rhizobium bacteria and leguminous plants.
Answer:
Nitrogen gas is available in plenty in the air but plants cannot use it in manner they can use carbon dioxide. They need nitrogen in soluble form. The bacterium called Rhizobium can take atmospheric nitrogen and convert it into soluble form. But Rhizobium cannot make its own food. So it lives in the roots of leguminous plants and provide them with nitrogen and in turn gets food and shelter from the plant.

Extra Questions for Class 7 Science Chapter 1 Long Answer Type

Question 1.
Differentiate between autotrophic and heterotrophic modes of nutrition.
Answer:
Autotrophic:

• This type of nutrition is found in green plants.
• Autotrophic organism can prepare their own food.
• In this mode of nutrition, carbon dioxide is utilized to prepare food in presence of sunlight.

Heterotrophic:

• This type of nutrition is found in some plants and all animals.
• Heterotrophic organisms cannot prepare their own food.
• They cannot use carbon dioxide to prepare food in presence of sunlight.

Question 2.
What is photosynthesis? Draw a schematic diagram to show photosynthesis.
Answer:
The process by which green plants containing chlorophyll prepare their own food with the help of sunlight, water and carbon dioxide is called photosynthesis.

Carbon dioxide from air is taken in through the tiny pores present on the surface of leaves. Water and minerals absorbed by the roots are transported to the leaves by the vessels which run throughout the plant.

The process can be represented as:

During the process of photosynthesis oxygen is released.
The carbohydrate so formed in the above process is ultimately converted into starch.

Question 3.
What is saprotrophic nutrition? Define the term saprotrophs.
Answer:
Organisms secrete digestive juices on the dead and decaying matter and convert it into a solution. Then they absorb the nutrients from it. This mode of nutrition in which organisms take in nutrients in solution form from dead and decaying matter is called saprotrophic nutrition.
Plants which use saprotrophic mode of nutrition are called saprotrophs.

Question 4.
Explain with the help of a labelled diagram ‘structure of a cell’.
Answer:

The body of a living organisms are made of tiny units called cells.
Cells can be seen only under the microscope. Some organisms are made of only one cell. The cell is enclosed by a thin outer boundary, called the cell membrane. Most cells have a distinct, centrally located spherical structure called the nucleus. The nucleus is surrounded by a jelly-like substance called cytoplasm.

Question 5.
Describe the function of stomata.
Answer:
The leaves take in carbon dioxide from the air through the small openings present on the surface of leaf called stomata (singular: stoma). Each stoma is bound by two crescent-shaped guard cells.

These cells draw water from the neighboring cells and swell up allowing the stomata to open. This allows carbon dioxide to enter the cells of the leaf through the stomata.

Question 6.
With the help of an experiment show that chlorophyll is necessary for photosynthesis.
Answer:

Take a variegated leaf like that of garden corton or Coleus. Boil the leaf in a test tube containing water and then alcohol in a water bath. Take out the leaf and wash it with warm water. Keep the leaf in a Petri plate and add 4-5 drops of iodine solution on it.

You will observe that only those portions of the leaf will turn blue-black which were green. The non-green part did not show any colour change. This shows chlorophyll is necessary for photosynthesis.

Nutrition in Plants HOTS Questions With Answers

Question 1.
Why most of the things are spoiled by fungi during rainy season only?
Answer:
Spores of fungi germinate and grow when they get wet and warm conditions. Rainy season provides them the hostile condition, so they grow and spoil most of the things in rainy season only.

Question 2.
Do leaves other than green color also have chlorophyll?
Answer:
Yes, leaves other than green color also have chlorophyll. A large amount of red, brown and other pigments mask the green color. Photosynthesis takes place in these leaves also.

Question 3.
If pitcher plant is green and carries out photosynthesis, then why does it feed on insects?
Answer:
Generally, pitcher plants grow in locations where the soil is too poor in minerals, particularly in nitrogen and phosphorous. So to fulfill its mineral requirements it feed on insects.

Question 4.
Potato and ginger are both underground parts that store food. Where is the food prepared in these plants?
Answer:
Food is prepared in the leaves of these plants and then it is transported to underground parts for storage.

Question 5.
Why farmers do not add fertilizers during cultivation of leguminous crop?
Answer:
Farmers do not add fertilisers during cultivation of leguminous crop because roots of leguminous plants have symbiotic association with a bacterium called Rhizobium which fixes atmospheric nitrogen into the soil.

Question 6.
Why Cuscuta have parasitic mode of nutrition?
Answer:
Cuscuta does not have chlorophyll, so it cannot synthesize its own food. Thus it obtains nutrition from its host through modified roots called haustoria. Haustoria penetrate into the host cell and derive their nutrition from there.

Extra Questions for Class 7 Science Chapter 1 Value Based Questions

Question 1.
During a rainy season Radhika’s, mother seems to be very busy in cleaning and keeping things in proper places. Radhika being feeling bored went to her mother and asked her what she is up to. Her mother affectionately explained her that this is the time when fungus grow very much. So she is keeping all things safe from their attack. Radhika on understanding this started helping her mother.
(a) What is fungi?
(b) What is the mode of nutrition in fungi?
(c) Why fungi appear suddenly during rainy season?
(d) How can you keep your things safe from fungi?
(e) What value of Radhika is shown here?
Answer:
(a) Fungi is single-celled or multicelled, spore-producing organisms which feed on organic matter.
(b) Fungi feed on dead and decaying matter so their mode of nutrition is saprotrophic.
(c) Spores of fungi germinate and grow when they get hot and wet condition. This condition is met during rainy season.
(d) We can keep our things safe from fungi by

• Keeping them in dry and clean places.
• Putting or wrapping them with suitable materials.
• Keeping food items in refrigerator and closing them with proper lids.

(e) Radhika is inquisitive, enthusiastic, and helpful.

Question 2.
Raman once saw Raghav planning of cutting all the trees around his house. Raman asked Raghav the reason for this step. Raghav replied that these trees do not provide him anything like fruits, timber, etc., so he is cutting them. Raman explained him though they are not providing him fruits, timber, flower, etc., but still they are very useful to all.
(a) How plants are still useful to all?
(b) List some items we get from plants.
(c) A cow ate all the leaves of a small plant but then also new leaves seen sprouting after a few days. How did the plant survived without leaves?
(d) What values of Raman and Raghav is shown here?
(e) What will you do if you also have a tree near your house which is of no use to you?
Answer:
(a) Plants give out oxygen and takes in carbon dioxide during the process of photosynthesis. Thus helps to keep the atmosphere clean.
(b) We get food, clothes, timber, fuel, medicines, fruit, flower, etc., from plants.
(c) Plant survived on the food stored in plant stem and roots for that time being still the leaves started sprouting.
(d) Raman is a good thinker, intelligent, eco-friendly with future vision. Whereas Raghav is self-oriented and ignorant.
(e) If it is of no use then also I will try to guard it because at least it will provide us with fresh air and shade.

NCERT Extra Questions for Class 7 Social Science SST: Here we are providing NCERT Extra Questions for Class 7 Social Science SST with Solutions Answers Chapter Wise Pdf free download of History, Geography, Civics, Economics. Students can get Class 7 Social Science NCERT Solutions, CBSE Class 7 Social Science Important Extra Questions and Answers designed by subject expert teachers.

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NCERT Class 7 Social Science Extra Questions and Answers

Access the links which are provided below and download CBSE NCERT Chapter Wise Extra Questions for Class 7 Social Science SST with answers and solutions pdf board examination preparation.

NCERT Class 7 Geography Extra Questions

Extra Questions for Class 7 Social Science Geography : Our Environment

1. Environment Class 7 Extra Questions
2. Inside Our Earth Class 7 Extra Questions
3. Our Changing Earth Class 7 Extra Questions
4. Air Class 7 Extra Questions
5. Water Class 7 Extra Questions
6. Natural Vegetation and Wild Life Class 7 Extra Questions
7. Human Environment: Settlement, Transport, and Communication Class 7 Extra Questions
8. Human Environment Interactions: The Tropical and the Subtropical Region Class 7 Extra Questions
9. Life in the Temperate Grasslands Class 7 Extra Questions
10. Life in the Deserts Class 7 Extra Questions

NCERT Class 7 History Extra Questions

Extra Questions for Class 7 Social Science History : Our Pasts – II

1. Tracing Changes Through A Thousand Years Class 7 Extra Questions
2. New Kings and Kingdoms Class 7 Extra Questions
3. The Delhi Sultans Class 7 Extra Questions
4. The Mughal Empire Class 7 Extra Questions
5. Rulers and Buildings Class 7 Extra Questions
6. Towns, Traders, and Craftsperson Class 7 Extra Questions
7. Tribes, Nomads and Settled Communities Class 7 Extra Questions
8. Devotional Paths to the Divine Class 7 Extra Questions
9. The Making of Regional Cultures Class 7 Extra Questions
10. Eighteenth-Century Political Formations Class 7 Extra Questions

NCERT Class 7 Civics Extra Questions

1. On Equality Class 7 Extra Questions
2. Role of the Government in Health Class 7 Extra Questions
3. How the State Government Works Class 7 Extra Questions
4. Growing Up as Boys and Girls Class 7 Extra Questions
5. Women Change The World-Class 7 Extra Questions
6. Understanding Media Class 7 Extra Questions
7. Markets Around Us Class 7 Extra Questions
8. A Shirt in the Market Class 7 Extra Questions
9. Struggles for Equality Class 7 Extra Questions

We hope the given NCERT Extra Questions for Class 7 Social Science SST with Solutions Answers Chapter Wise Pdf free download of History, Geography, Civics will help you. If you have any query regarding CBSE Class 7 Social Science Extra Questions, drop a comment below and we will get back to you at the earliest.