9th class Biology, Chapter 8: Plant Physiology MCQs

1. The primary function of root hairs is:

1. (A) Transport of nutrients
2. (B) Storage of food
3. (C) Increase surface area for absorption ✓
4. (D) Synthesis of proteins

2. Water moves from the soil into root cells by:

1. (A) Osmosis ✓
2. (B) Active transport
3. (C) Diffusion
4. (D) Bulk flow

3. The transpiration is regulated by:

1. (A) Mesophyll
2. (B) Guard cells ✓
3. (C) Xylem
4. (D) Phloem

4. In most plants the food is transported in the form of:

1. (A) Glucose
2. (B) Sucrose ✓
3. (C) Starch
4. (D) Maltose

5. What is TRUE according to the pressure flow mechanism of food transport?

1. (A) Water enters the source, creating pressure ✓
2. (B) Water is pulled from the sink
3. (C) Movement of food in phloem is due to gravity
4. (D) Solutes move from low to high concentration

6. Succulent organs are present in:

1. (A) Xerophytes ✓
2. (B) Hydrophytes
3. (C) Mesophytes
4. (D) Halophytes

7. Transport in plants means the movement of:

1. (A) water, nutrients, hormones and waste products ✓
2. (B) only water
3. (C) only food
4. (D) only gases

8. In land plants (except mosses and liverworts) water and salts are transported by:

1. (A) xylem ✓
2. (B) phloem
3. (C) cuticle
4. (D) stomata

9. Food prepared by the leaves is transported by:

1. (A) phloem ✓
2. (B) xylem
3. (C) epidermis
4. (D) root hairs

10. The movement of ions from a region of lower to a region of higher concentration using energy is called:

1. (A) active transport ✓
2. (B) passive transport
3. (C) osmosis
4. (D) diffusion

11. Which of the following is an example of passive transport?

1. (A) Diffusion ✓
2. (B) Uptake of salts by root hairs
3. (C) Loading of sucrose into sieve tubes
4. (D) Uptake of potassium ions by guard cells

12. Osmosis is the movement of water through a semi-permeable membrane from a region of:

1. (A) lower solute concentration to higher solute concentration ✓
2. (B) higher solute concentration to lower solute concentration
3. (C) lower pressure to higher pressure
4. (D) cold to hot

13. The outermost covering of a root is the:

1. (A) epidermis ✓
2. (B) cortex
3. (C) endodermis
4. (D) pericycle

14. Root hairs take in salts by:

1. (A) active transport ✓
2. (B) osmosis
3. (C) diffusion only
4. (D) bulk flow

15. Water moves from the soil into root hairs by:

1. (A) osmosis ✓
2. (B) active transport
3. (C) transpiration
4. (D) translocation

16. The innermost boundary of the root cortex is the:

1. (A) endodermis ✓
2. (B) epidermis
3. (C) pericycle
4. (D) xylem

17. The narrow layer present on the inner side of the endodermis is the:

1. (A) pericycle ✓
2. (B) cortex
3. (C) epidermis
4. (D) phloem

18. The loss of water in the form of vapours from the plant surface is called:

1. (A) transpiration ✓
2. (B) translocation
3. (C) osmosis
4. (D) photosynthesis

19. Special openings in the stems of some plants through which transpiration occurs are called:

1. (A) lenticels ✓
2. (B) stomata
3. (C) root hairs
4. (D) guard cells

20. Most of the transpiration occurs through:

1. (A) stomata ✓
2. (B) cuticle
3. (C) lenticels
4. (D) root hairs