Gujarat Board GSEB Textbook Solutions Class 7 Science Chapter 2 Nutrition in Animals Textbook Questions and Answers, Notes Pdf.
Gujarat Board Textbook Solutions Class 7 Science Chapter 2 Nutrition in Animals
Gujarat Board Class 7 Science Nutrition in Animals Textbook Questions and Answers
Question 1.
Fill in the blanks:
(a) The main steps of nutrition in humans and ________, ________, ________, ________ and ________.
(b) The largest gland in the human body is ________.
(c) The stomach releases hydrochloric acid and ________ juices which act on food.
(d) The inner wall of the small intestine has many finger-like outgrowths called ________.
(e) Amoeba digests its food in the ________.
Answer:
(a) ingestion, digestion, absorption, assimilation, egestion
(b) liver
(c) digestive
(d) villi
(e) food vacuole.
Question 2.
Mark ‘T’ if the statement is true and ‘F’ if it is false:
(a) Digestion of starch starts in the stomach.
(b) The tongue helps in mixing food with saliva.
(c) The gall bladder temporarily stores bile.
(d) The ruminants bring back swallowed grass into their mouth and chew it for some time.
Answer:
(a) False
(b) True
(c) True
(d) True
Question 3.
Tick (S) mark the correct answer in each of the following:
(a) Fat is completely digested in the
(i) stomach
(ii) mouth
(iii) small intestine
(iv) large intestine
Answer:
(iii) small intestine
(b) Water from the undigested food is absorbed mainly in the
(i) stomach
(ii) foodpipe
(iii) small intestine
(iv) large intestine
Answer:
(iv) large intestine
Question 4.
Match the items of Column I with those given in Column II:
| Column I Food components | Column II Produce(s) of digestion |
| (a) Carbohydrates | (i) Fatty acids and glycerol |
| (b) Proteins | (ii) Sugar |
| (c) Fats | (iii) Amino acids |
Answer:
| Column I Food components | Column II Produces) of digestion |
| (a) Carbohydrates | (i) Sugar |
| (b) Proteins | (ii) Amino acids |
| (c) Fats | (iii) Fatty acids and glycerol |
Question 5.
Wdiat are villi? What is their location and function?
Answer:
The finger like projections in the inner walls of the small intestine is called villi. These are found in small intestine.
Function: The villi increase the surface area for absorption of the digested food.
Question 6.
Where is the bile produced? Which component of the food does it help to digest?
Answer:
Bile is produced in liver. The bile juice is stored in sac called the gall bladder. It helps in the digestion of fats.
Question 7.
Name the type of carbohydrate that can be digested by ruminants but not by humans. Give the reason also.
Answer:
Cellulose is the carbohydrate that can be digested by ruminants. Ruminants have large sac like structure between the small intestine and large intestine. The cellulose of the food is digested by the action of certain bacteria which are not present in humans.
Question 8.
Why do we get instant energy from glucose?
Answer:
Because it easily breaks down in the cell with the help of oxygen which provides instant energy to the organism. Glucose does not need digestion, it is directly absorbed into the blood.
Question 9.
Which part of the digestive canal is involved in:
(i) absorption of food ________.
(ii) chewing of food ________.
(iii) killing of bacteria ________.
(iv) complete digestion of food ________.
(v) formation of faeces ________.
Answer:
(i) Small intestine
(ii) Mouth
(iii) Stomach
(iv) Small intestine
(v) Large intestine
Question 10.
Write one similarity and one difference between the nutrition in amoeba and human beings.
Answer:
Similarity: The digestive juices in amoeba are secreted into food vacuole and in human beings the digestive juices are secreted in stomach and small intestine. Then the juices convert complex food into simpler soluble and absorbable substances. Difference: Amoeba captures the food with the help of pseudopodia and engulf it. In human beings food is taken by the mouth.
Question 11.
Match the items of Column I with suitable items in Column II.
| Column I | Column II |
| (a) Salivary gland | (i) Bile juice secretion |
| (b) Stomach | (ii) Storage of undigested food |
| (c) Liver | (iii) Saliva secretion |
| (d) Rectum | (iv) Acid release |
| (e) Small intestine | (v) Digestion is completed |
| (f) Large intestine | (vi) Absorption of water |
| (vii) Release of faeces |
Answer:
| Column I | Column II |
| (a) Salivary gland | (iii) Saliva secretion |
| (b) Stomach | (iv) Acid release |
| (c) Liver | (i) Bile juice secretion |
| (d) Rectum | (ii) Storage of undigested food |
| (e) Small intestine | (v) Digestion is completed |
| (f) Large intestine | (vi) Absorption of water |
Question 12.
Label Fig. of the digestive system, (as given in the NCERT Textbook Exercise)
Answer:
Question 13.
Can we survive only on raw, leafy vegetables/grass? Discuss.
Answer:
We know that the animals, fungi, bacteria, non-green plants and human being do not .have the ability to make their own food. They depend upon autotrophs for their food directly or indirectly. The green plant (leafy vegetables/grass) trap solar energy and make their own food in the form of glucose. So, we can say that leafy vegetables and grass can provide sufficient energy to help us survive. But, we cannot survive only on raw, ready vegetables since they have cellulose and humans are not able to digest cellulose.
Extended Learning – Activities And Project
Question 1.
Visit a doctor and find out:
(i) Under what conditions does a patient need to be on a drip of glucose?
(ii) Till when does a patient need to be given glucose?
(iii) How does glucose help the patient recover?
Write the answers in your notebook.
Answer:
(i) (a) When patient is unable to intake food or digest food, or
(b) When there is emergency to supply energy to a patient.
(ii) Till the patient is out of danger or crisis is over.
(iii) Glucose does not need digestion and is directly given into the blood. Breakdown of glucose in the cells instantly supplies energy. This helps the patient to recover quickly.
Question 2.
Find out what vitamins are and get the following information.
(i) Why are vitamins necessary in the diet?
(ii) Which fruits or vegetables should be eaten regularly to get vitamins? Write a one-page note on the information collected by you. You may take help of a doctor, a dietician, your teacher or any other person, or from any other source.
Answer:
Vitamins: They are a group of organic compounds which are present in many foods and are essential for normal health. They sire required in small quantities.
(i) Vitamins help in protecting our body against diseases. Vitamins also help in keeping our eyes, bones, teeth and gums healthy.
(ii) We should take the following fruits or vegetables to get vitamins. Carrot, spinach, leafy vegetables, citrus fruits like orange, tomatoes, papaya, banana, cauliflower, gourds, beans, genninating grams, pineapple etc. It is very important to eat seasonal fruits and vegetables. Students are suggested to do it themselves.
Question 3.
Collect data from your friends, neighbours and classmates to know more about “milk teeth”.
Tabulate your data. One way of doing it is given below:
Find out from at least twenty children and find the average age at which children lose the milk teeth. You may take help of your friends.
Answer:
Do yourself with the help of friends, teachers and parents.