NCERT Solutions for Class 7 Science Chapter 11 Transportation in Animals and Plants

Exercises

Question:- 1. Match structures given in Column I with functions given in Column II.

Answer:-

Question:- 2. Fill in the blanks.

(i) The blood from the heart is transported to all parts of the body by the ___________.

(ii) Haemoglobin is present in cells___________.

 (iii) Arteries and veins are joined by a network of___________.

(iv) The rhythmic expansion and contraction of the heart is called___________.

(v) The main excretory product in human beings is___________.

(vi) Sweat contains water and___________.

(vii) Kidneys eliminate the waste materials in the liquid form called___________.

(viii) Water reaches great heights in the trees because of suction pull caused by___________.

Answer:-

(i) The blood from the heart is transported to all parts of the body by the arteries.

(ii) Haemoglobin is present in cells red blood cells.

 (iii) Arteries and veins are joined by a network of capillaries.

(iv) The rhythmic expansion and contraction of the heart is called heartbeat.

(v) The main excretory product in human beings is urea.

(vi) Sweat contains water and salts.

(vii) Kidneys eliminate the waste materials in the liquid form called urine.

(viii) Water reaches great heights in the trees because of suction pull caused by transpiration.

Question:- 3. Choose the correct option:

(a) In plants, water is transported through

(i) xylem                  (ii) phloem

(iii) stomata            (iv) root hair

Answer:- (i) xylem                 

(b) Water absorption through roots can be increased by keeping the plants

(i) in the shade

(ii) in dim light

(iii) under the fan

(iv) covered with a polythene bag

Answer:- (iii) under the fan

Question:- 4. Why is transport of materials necessary in a plant or in an animal? Explain.

Answer:- Material transportation is vital for plants and animals because it allows nutrients and oxygen to reach all sections of the body. The body will not be able to survive if vital nutrients and oxygen are not transported throughout it.

Question:- 5. What will happen if there are no platelets in the blood?

Answer:- The blood platelets are responsible for the clotting of the blood. When some injury happens blood starts pouring. It does, however, clot on its own. The blood will not be able to clot and will continue to flow if platelets are not present. Death occurs when there is a significant loss of blood.

Question:- 6. What are stomata? Give two functions of stomata.

Answer:- Tiny pores present on the surface of the leaf are known as stomata.

Two functions of stomata are following:-

It helps in exchange of gases.

It helps in evaporation of water.

Question:- 7. Does transpiration serve any useful function in the plants? Explain.

Answer:- Transpiration serves the following functions in plants

1. It helps in the reduction of plant temperature, hence minimising heat damage.
2. Helps in transpiration pull, which helps in raining water in higher plants.
3. It also results in plant water loss.

Question:- 8. What are the components of blood?

Answer:- The components of blood are red blood cells, white blood cells, platelets and plasma.

Question:- 9. Why is blood needed by all the parts of a body?

Answer:- Blood is needed by all the parts because it contains the digested food and oxygen.  It carries oxygen and digested food to various parts of the body, providing them with vital energy that allows the body to perform its activities.

Question:- 10. What makes the blood look red?

Answer:- The red colour of blood comes from a red pigment called haemoglobin. This pigment aids in blood transporting oxygen to various regions of the body.

Question:- 11. Describe the function of the heart.

Answer:- Blood with carbon dioxide is received via the right auricle and ventricle from all areas of the body. The blood is subsequently pushed to the lungs, where it is purified. Gases are exchanged in the lungs, and purified blood is returned to the left auricle. It pumps the blood to the left ventricle, which then distributes the purified blood to all regions of the body via arteries.

Question:- 12. Why is it necessary to excrete waste products?

Answer:- When our body cells perform their functions, certain waste products are released. These waste products are  poisonous and hence need to be removed from the body.