Chhattisgarh State Class 7 Science Chapter 14 Solution

Chhattisgarh State Board Class 7 Science Chapter 14 Excretion in Living Organisms Exercise Multiple Choice, Questions and Answers here.

(1) Choose the correct answer –

(1) Unwanted substances are filtered from the blood by –

(a) Heart

(b) Lung

(c) Kidney

(d) Stomach

Answer:- (c) Kidney.

(2) The main excretory substance in man is –

(a) Uric acid

(b) Urea

(c) Water 

(d) Sweat

Answer:- (b) Urea.

(3) In bird dropping the colour of uric acid is –

(a) Black

(b) White

(c) Green

(d) Green & white

Answer:- (b) White.

(4) In our body, which organ is responsible for conversion of ammonia to urea –

(a) Liver

(b) Kidney

(c) Lungs

(d) Heart

Answer:- (a) Liver.

(5) In which organism does ammonia get directly dissolved in water through the body surface –

(a) Mosquito

(b) Parrot

(c) Lizard

(d) Amoeba

Answer:- (d) Amoeba.

(2) Answer the following question:-

(1) Why is necessary to remove unwanted metabolic products from the body?

Answer:- (1) In body there are waste products which are toxic remain inside it for a long time it will be harmful for body

(2) Therefore, it is necessary to remove them from the body.

(2) Where are the kidney situated?

Answer:- Kidneys are situated just below the diaphragm, inside the abdomen on either side of the vertebral column.

(3) How is urine formed?

Answer:- (1) Ammonia gas cannot be removed directly from the body. It reaches the liver along with blood.

(2) Ammonia gas and carbon dioxide combine to form urea.

(3) Urea reaches the kidneys along with the blood, where it is filtered and removed from the body as urine.

(4) Urine consist of urea and water.

(4) Name some of the excretory substances formed in plant.

Answer:- Excretory substance formed in plant are –

(1) Gum

(2) Rubber

(5) How does excretion take place in birds and insects?

Answer:- (1) In birds and insects, ammonia is converted to solid uric acid.

(2) These organisms excrete solid uric acid. Bird usually drop white and black in colour.

(3) The white part in bird dropping is uric acid, and the black part consists of undigested food.

(6) Draw a labeled diagram of the excretory system in human beings.