Does transpiration serve any useful function in the plants? Explain.
The process of Transpiration is the loss of water from leaves that serves very useful function in the plants because it generates s ‘suction force’ in xylem which can pull water from the roots up to great height in the tall trees which is known as ascent of sap.
Another function of transpiration is that it keeps the plant cool in higher temperature by the evaporation. The rate of transpiration increase in moving air because this carries away water vapour from leaves as fast as it comes out of stomata. Higher vapour pressure differences between leaf air spaces and the external air increases the transpiration rate. And, when the rate of transpiration increases, the rate of absorption of water through the roots also get increased. Thus, by keeping a plant under the fan, water absorption through roots can be increased.
Popular Questions of Class 7 Science
- Q:-
Classify the changes involved in the following processes as physical or chemical changes:
(a) Photosynthesis
(b) Dissolving sugar in water
(c) Burning of coal
(d) Melting of wax
(e) Beating aluminium to make aluminium foil
(f ) Digestion of food - Q:-
Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down Across
(D) 1 : Thorough washing (A) 1 : Keeps warm
2 : Animal fibre 2 : Its leaves are eaten by silkworms
3 : Long thread like structure 3 : Hatches from egg of moth
- Q:-
Sketch the cross section of soil and label the various layers.
- Q:-
Here is a crossword puzzle: Good luck!
Across
3. Liquid waste products
4. Solid waste extracted in sewage treatment
6. A word related to hygiene
8. Waste matter discharged from human bodyDown
1. Used water
2. A pipe carrying sewage
5. Micro-organisms which causes cholera
7. A chemical to disinfect water - Q:-
Take three test-tubes. Fill æth of each with water. Label them A, B and C. Keep a snail in test-tube A, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of CO2?
- Q:-
Sketch the reproductive parts of a flower.
- Q:-
Solve the following crossword puzzle with the clues given:
Across
2. Plantation prevents it.
5. Use should be banned to avoid soil pollution.
6. Type of soil used for making pottery.
7. Living organism in the soil.Down
1. In desert soil erosion occurs through.
3. Clay and loam are suitable for cereals like.
4. This type of soil can hold very little water.
5. Collective name for layers of soil. - Q:-
Describe how crystals of copper sulphate are prepared.
- Q:-
Match the items in Column I with those in Column II:
Column I Column II
(i) A home for living organisms (a) Large particles
(ii) Upper layer of the soil (b) All kinds of soil
(iii) Sandy soil (c) Dark in colour
(iv) Middle layer of the soil (d) Small particles and packed tight (v) Clayey soil (e) Lesser amount of humus - Q:-
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.
Recently Viewed Questions of Class 7 Science
- Q:-
Mark 'T' if the statement is true and 'F' if it is false:
(a) We can obtain an enlarged and erect image by a convex mirror. (T/F)
(b) A concave lens always form a virtual image. (T/F)
(c) We can obtain a real, enlarged and inverted image by a concave mirror. (T/F)
(d) A real image cannot be obtained on a screen. (T/F)
(e) A concave mirror always form a real image. (T/F) - Q:-
You have been asked to maintain a garden. How will you minimise the use of water?
- Q:-
What are stomata? Give two functions of stomata.
- Q:-
Tick the correct answer:
(a) Amarbel is an example of:
(i) autotroph (ii) parasite (iii) saprotroph (iv) host(b) The plant which traps and feeds on insects is:
(i) Cuscuta (ii) china rose (iv) pitcher plant (iv) rose - Q:-
Sketch the cross section of soil and label the various layers.
- Q:-
Stainless steel pans are usually provided with copper bottoms. The reason for this could be that
(a) copper bottom makes the pan more durable.
(b) such pans appear colourful.
(c) copper is a better conductor of heat than the stainless steel.
(d) copper is easier to clean than the stainless steel. - Q:-
Which one of the following place is unlikely to be affected by a cyclone.
(i) Chennai (ii) Mangaluru (Mangalore) (iii) Amritsar (iv) Puri
- Q:-
Look at Fig. 4.13. Mark where the heat is being transferred by conduction, by convection and by radiation.
- Q:-
Describe the function of the heart.
- Q:-
Classify the following as motion along a straight line, circular or oscillatory motion:
(i) Motion of your hands while running.
(ii) Motion of a horse pulling a cart on a straight road.
(iii) Motion of a child in a merry-go-round.
(iv) Motion of a child on a see-saw.
(v) Motion of the hammer of an electric bell.
(vi) Motion of a train on a straight bridge.
- NCERT Chapter