NCERT Solutions for Class 7 Science Chapter 2 - Nutrition in Animals

NCERT Solutions for Class 7 Science Chapter 2 – Nutrition in Animals. Furthermore, here we’ve provided you with the latest solution for Class 7 Science Chapter 2 – Nutrition in Animals. As a result here you’ll find solutions to all the exercises. This NCERT Class 7 solution will help you to score good marks in your exam.

Students can refer to our solution for NCERT Class 7 Science Chapter 2 – Nutrition in Animals. The Chapter 2 Solution of NCERT will help students prepare for the exams and easily crack the exam. Below we’ve provided you with the latest solution.

NCERT Solutions for Class 7 Science Chapter 2 – Nutrition in Animals Pdf Download

Answers to Questions On Page no. 20 of Ncert Class 7 Science Chapter 2 – Nutrition in Animals

Q1: Fill in the blanks:

Answer:

The main steps of nutrition in humans are ingestion , digestion, absorption , assimilation and egestion.
The largest gland in the human body is liver.
The stomach releases hydrochloric acid and digestive juices which act on food.
The inner wall of the small intestine has many finger-like outgrowths called villi .
Amoeba digests its food in the _food vacuole_.

Q2: Mark ‘T’ if the statement is true and ‘F’ if it is false:

Answer:

Digestion of starch starts in the stomach. (F)
The tongue helps in mixing food with saliva. (T)
The gall bladder temporarily stores bile. (T)
The ruminants bring back swallowed grass into their mouth and chew it for some time. (T)

Q3: Tick ( ) mark the correct answer in each of the following:

Answer:

(a) Fat is completely digested in the

stomach
mouth
small intestine
large intestine

(b) Water from the undigested food is absorbed mainly in the

stomach
food pipe
small intestine
large intestine

Q4: Match the items of Column I with those given in Column II:

Column I	Column II
Food components	Product(s) of digestion
Carbohydrates	Sugar
Proteins	Amino acids
Fats	Fatty acids and glycerol

Q5: What are villi? What is their location and function?

Answer: Villi are tiny finger-like projections originating from the walls of the small intestine. They increase the surface area for absorption of the digested food. The blood vessels present inside the villi can absorb the nutrients from the digested food.

Q6: Where is the bile produced? Which component of the food does it help to digest?

Answer: Liversecretes the bile juice which is stored in the gall bladder. Bile plays an important role in the digestion of fats.

Q7: Name the type of carbohydrate that can be digested by ruminants but not by humans. Give the reason also.

Answer: Cellulose is a type of carbohydrate that can be digested by ruminants and not by humans. Ruminants have a large sac-like structure between small and large intestine where the food containing cellulose is digested by the action of certain bacteria. On the other hand, humans cannot digest cellulose, as the cellulose digesting enzymes are absent in them.

Q8: Why do we get instant energy from glucose?

Answer: Glucose is a simple sugar. Carbohydrates, when consumed, have to be digested into glucose. As glucose can be easily absorbed in blood, it provides energy to the body. Hence, when glucose is directly taken, it does not have to be digested and thus acts as an instant source of energy.

Q9: Which part of the digestive canal is involved in:

Answer:

absorption of food – small intestine
chewing of food – buccal cavity
killing of bacteria – stomach
complete digestion of food – small intestine
formation of faeces – large intestine

Q10: Write one similarity and one difference between the nutrition in Amoeba and human beings.

Answer:

Similarity between nutrition in Amoeba and human beings:

Both Amoeba and humans require energy for the growth and maintenance of their bodies. This energy is derived from the food that they eat. The food that they consume is always in a complex form and is therefore broken down into simpler forms by the process of digestion. Hence, both these organisms are heterotrophs.

Differences between nutrition in Amoeba and human beings:

Digestion in Humans	Digestion in Amoeba
Humans have a mouth and a complex	Mouth and digestive system are digestive absent in Amoeba.
Digestive juices are secreted in the buccal cavity, stomach, and small intestine.	Digestive juices are secreted in the food vacuole.
Digestion of carbohydrates, proteins, and fats are digested in separate regions. .	All the food components digestion starts in the food vacuole.

Q11: Label the following figure of the digestive system.

Answer:

Q12: Can we survive only on raw, leafy vegetables/grass? Discuss.

Answer: No. Humans cannot survive only on raw, leafy vegetables, or grass. It is because the grass is rich in cellulose, which is a type of carbohydrate that humans are not able to digest due to the absence of cellulose-digesting enzymes.