PLANT PHYSIOLOGY (Part-I)

1. Which Indian scientist invented the instrument to measure the growth of plants? [S.S.C. Online Stenographer 13.09.2017 (Shift-I)]

(a) C. V. Raman
(b) Jagdish Chandra Bose
(c) Jayant Narlikar
(d) Birbal Sahni

Correct Answer: (b) Jagdish Chandra Bose

Solution:Jagdish Chandra Bose -
Sir Jagdish Chandra Bose invented the crescograph, an instrument used to measure the growth of plants.

2. The elements known as primary nutrients for plants- [S.S.C. Online Graduate Level (T-I) 6.09.2016 (Shift-II)]

(a) Nitrogen, Phosphorus and Potassium
(b) Nitrogen, Oxygen and Silicon
(c) Potassium, Boron and Nitrogen
(d) Nitrogen, Phosphorus and Iron

Correct Answer: (a) Nitrogen, Phosphorus and Potassium

Solution:Nitrogen, Phosphorus and Potassium -
These three elements (N, P, K) are considered the primary macronutrients essential for plant growth.

3. By which process does water come out as water vapor from the leaf? [S.S.C. MTS (T-I) 19.09.2017 (Shift-III)]

(a) Transpiration
(b) evaporation
(c) condensation
(d) sublimation

Correct Answer: (a) Transpiration

Solution:Transpiration -
Transpiration is the process by which water exits the plant as water vapor, primarily through the leaves.

4. Tiny pores present on the surface of leaves are known as: [S.S.C. Online MTS (T-I) 22.10.2021 (Shift-III)]

(a) Cytoplasm
(b) Nucleus
(c) Mitochondria
(d) Stomata

Correct Answer: (d) Stomata

Solution:Stomata -
Stomata are the tiny pores present on the surface of leaves that facilitate gas exchange and transpiration.

5. Which part of the plant allows for the uptake of carbon dioxide and limits the loss of water due to evaporation? [S.S.C. Online MTS (T-I) 18.10.2021 (Shift-III)]

(a) Stipule
(b) Lamina
(c) Petiole
(d) Stomata

Correct Answer: (d) Stomata

Solution:Plants have tiny pore-forming structures on the surface of leaves called ‘stomata’. These stomata absorb carbon dioxide from the atmosphere and control the process of transpiration as per the requirement. As a result, the resulting water loss is limited.

6. Tiny pores present on the surface of leaves are known as: [S.S.C. Online C.H.S.L. (T-I) 13.08.2021 (Shift-III)]

(a) Cytoplasm
(b) Stomata
(c) Nucleus
(d) Mitochondria

Correct Answer: (b) Stomata

7. What are the small pores on the lower surface of the leaf called? [S.S.C. Online Constable GD 12.02.2019 (Shift-I)]

(a) Pore
(b) Cilia
(c) Stomata
(d) Opening

Correct Answer: (c) Stomata

Solution:Stomata -
Stomata are indeed the small pores typically found on the lower surface of the leaf.

8. Evaporation of water takes place in which part of plants? [S.S.C. Online CHSL (T-I) 21.01.2017 (Shift-I)]

(a) Stem
(b) Stomata
(c) Branch
(d) Fruit

Correct Answer: (b) Stomata

Solution:Stomata -
The evaporation of water during transpiration primarily occurs through the stomata on the leaves.

9. _____ are a group of chemicals that influence cell division and shoot formation. [S.S.C. Online CHSL (T-I) 22.01.2017 (Shift-I)]

(a) Cytokinins
(b) Gibberellins
(c) Domins
(d) Auxins

Correct Answer: (a) Cytokinins

Solution:Cytokinins -
Cytokinins are plant hormones that promote cell division and shoot formation.

10. Rate of transpiration in a dorsiventral leaf is [S.S.C. Online MTS (T-I) 12.10.2017 (Shift-III)]

(a) Lesser at the surface
(b) Greater at the lower surface
(c) Equal at both the surfaces
(d) None of these

Correct Answer: (b) Greater at the lower surface

Solution:Greater at the lower surface -
In a dorsiventral leaf (a typical dicot leaf), there are usually more stomata on the lower surface, leading to a higher rate of transpiration there.