CBSE Class 7 Science Life Processes in Plants (Class 7 NCERT New) Quiz 7

1. A scientist covers the leaves of a plant with a material that blocks carbon dioxide but allows sunlight and water to reach the plant. What would happen to the rate of photosynthesis, and why?

A Photosynthesis would increase because more water is available B Photosynthesis would remain the same because sunlight is still present C Photosynthesis would stop or decrease significantly because carbon dioxide is a necessary reactant D Photosynthesis would increase because the plant would use stored nitrogen instead

2. A plant is growing in soil that lacks minerals but has plenty of water and sunlight. Using your knowledge of plant transport tissues, predict what problem the plant might face and explain which tissue is involved.

A The phloem would fail to transport glucose, causing the leaves to turn yellow B The xylem would be unable to deliver minerals to the leaves, affecting the plant's ability to produce chlorophyll and carry out photosynthesis C The stomata would close permanently, preventing gas exchange D The roots would stop absorbing water because minerals are needed for water absorption

3. Two plants of the same species are grown: one through seed germination (generative reproduction) and one through stem cutting (vegetative reproduction). A student claims the plant grown from a stem cutting will be genetically identical to the parent plant, but the plant grown from a seed will not. Is the student correct? Why?

A No, because both methods always produce genetically identical plants B Yes, because vegetative reproduction copies the parent's genetic material exactly, while generative reproduction combines genetic material from two parents, creating variation C No, because seeds always produce plants identical to the parent D Yes, because stem cuttings use a different type of DNA than seeds

4. A forest is being cut down, and large numbers of trees are being removed. Using your knowledge of photosynthesis, explain what impact this would have on the levels of oxygen and carbon dioxide in the atmosphere.

A Oxygen levels would increase because fewer plants means less carbon dioxide is absorbed B Carbon dioxide levels would decrease because fewer plants are releasing it during respiration C Oxygen levels would decrease and carbon dioxide levels would increase because fewer plants are performing photosynthesis to convert into D There would be no change because animals produce enough oxygen to compensate

5. A plant biologist is studying two plants: Plant A reproduces only through vegetative reproduction, and Plant B reproduces only through generative reproduction. A new disease appears in the environment. Which plant population is more likely to survive the disease over many generations, and why?

A Plant A, because vegetative reproduction produces more offspring in a shorter time B Plant B, because generative reproduction creates genetic variation, increasing the chance that some individuals will be resistant to the disease C Plant A, because identical plants are stronger and more resistant to disease D Plant B, because seeds are protected by a hard coat that prevents disease

6. What process do plants use to make their own food?

A Photosynthesis B Fermentation C Transpiration D Respiration

7. What part of the plant absorbs water and nutrients from the soil?

A Stems B Leaves C Flowers D Roots

8. Which pigment is responsible for the green color in plants?

A Xanthophyll B Chlorophyll C Carotene D Anthocyanin

9. What is the name of the process by which plants release oxygen?

A Fermentation B Respiration C Photosynthesis D Transpiration

10. What type of plant reproduces using seeds?

A Mosses B Seed plants C Flowering plants D Fungi