Question 1.
Match structures given in Column I with functions given in Column II.
Column I
(i) Stomata
(ii) Xylem
(iii) Root hairs
(iv) Phloem
Column II
(a) Absorption of water
(b) Transpiration
(c) Transport of food
(d) Transport of water
(e) Synthesis of carbohydrates
Solution:
(i)-(b)
(ii)-(d)
(iii)-(a)
(iv)-(c).
Question 2.
Fill in the blanks.
- The blood from the heart is transported to all parts of the body by the ………..
- Hemoglobin is present in ………. cells.
- Arteries and veins are joined by a network of ………..
- The rhythmic expansion and contraction of the heart is called ………..
- The main excretory product in human beings is ………..
- Sweat contains water and ………..
- Kidneys eliminate the waste materials in the liquid form called ………..
- The water reaches great heights in the trees because of suction pull caused by ………..
Solution:
- arteries
- red blood cells
- capillaries
- heartbeat
- urea
- salts
- urine
- transpiration.
Question 3.
Choose the correct option :
(a) In plants, water is transported through
(i) Xylem
(ii) Phloem
(iii) Stomata
(iv) Root hair
(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
Solution:
(a)-(i) xylem
(b)-(ii) in dim light.
Question 4.
Why is the transport of materials necessary in a plant or in an animal? Explain.
Solution:
In plants and animals, the transport of materials is necessary for the following reasons:
- Animals need to transport food and water from the small intestine and oxygen from the lungs to all other body parts.
- Animals need to transport the wastes from where they are produced to parts from where they can be removed.
- Plants need to transport the food from leaves and water and minerals to all other parts of the plant.
Question 5.
What will happen if there are no platelets in the blood?
Solution:
Blood cannot clot without the platelets. So, if there is any cut, blood will continue to flow out and ultimately the person die.
Question 6.
What are stomata? Give two functions of stomata.
Solution:
Small pores in leaves of plants are called stomata. Functions of stomata are :
- absorption of oxygen from air.
- removal of excess water by transpiration.
Question 7.
Does transpiration serve any useful function in the plants? Explain?
Solution:
Yes. Transpiration is useful for the plants in the following ways:
- The evaporation of water from leaves generates a suction pull which can pull water to great heights in the tall trees.
- Provides cooling to the plant.
Question 8.
What are the components of blood?
Solution:
Red blood cells, white blood cells, platelets, and plasma.
Question 9.
Why is blood needed by all the parts of a body?
Solution:
All the parts of the body need food and oxygen which is carried to them by the blood. They also release their wastes into the blood which is then transported to the parts from where they can be removed.
Question 10.
What makes the blood look red?
Solution:
The presence of hemoglobin.
Question 11.
Describe the function of the heart.
Solution:
The heart acts as a pumping organ for the transport of blood. The rhythmic contraction and relaxation of the various chambers of the heart maintain the circulation of blood and transport of substances to the different parts of the body.
Question 12.
Why is it necessary to excrete waste products?
Solution:
When our cells perform their functions, certain waste products are released. These are toxic and their accumulation in the body may lead to fatal consequences, hence they need to be removed.
Question 13.
Draw a diagram of the human excretory system and label the various parts.
Solution: