Anatomy of Flowering Plants PYQ's

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 Previous Year Questions:

1. Bulliform cells are responsible for                                                                                             (2024)

A) Inward curling of leaves in monocot
B) Protecting the plant from salt stress.
C) Increased photosynthesis in monocots.
D) Providing large space for storage of sugar.

Ans. A - Inward curling of leaves in monocot.
Explanation: In grasses certain adaxial epidermal cell along the veins modify themselves into large, empty, colorless cells. These are called bulliform cells. When the bulliform cells in the leaves have absorbed water and are turgid, the leaf surface is exposed. When they are flaccid due to water stress, they make the leaves curl inwards to minimize water loss.

2. In the given figure, which component has thin outer walls and highly thickened inner walls?     (2024)

A) C      B) D
C) A      D) B

Ans. A - C
Explanation: The given figure is of stomata with bean shaped guard cells. A is epidermal cells. B is subsidiary cell. C is guard cell and D is stomatal pore. The outer walls of guard cells are thin and the inner walls are highly thickened.

3. Given below are two statements:                                                                                             (2024)

Statement I: Parenchyma is living but collenchyma is dead tissue.
Statement II: Gymnosperms lack xylem vessels but presence of xylem vessels is the characteristic of angiosperms.

In the light of the above statements, choose the correct answer from the options given below.

1) Both statement I and statement II are true.
2) Both statement I and statement II are false.
3) Statement I is true but statement II is false.
4) Statement I is false but statement II is true.

Ans. 4- Statement I is false but statement II is true.

Explanation: Collenchyma is also a living tissue and hence statement I is false. Gymnosperms lack xylem vessels but presence of xylem vessels is characteristic of angiosperms and hence statement II is true.



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