Question 10
Guard cells help in
A
guttation
B
transpiration
C
protection against grazing
D
fighting against infection
Question 11
Which of the following is NOT an essential micronutrient?
A
Boron
B
Calcium
C
Manganese
D
Nickel
Question 12
Deficiency of molybdenum causes
A
chlorosis of leaves
B
bending of leaf tip
C
poor development of vascular system
D
mottling and necrosis of leaves
Question 13
What are micronutrients?
A
They are as important in nutrition as the macronutrients.
B
They are more important in nutrition than macronutrients.
C
They may be omitted from culture media without any detrimental effect on the plant.
D
They are called ‘micro’ because they play only a minor role in plant nutrition.
Question 14
The leaves become yellow due to the deficiency of
A
iron and magnesium
B
potassium and calcium
C
nitrogen and copper
D
zinc and boron
Question 15
Rate of transpiration increases
A
in water
B
in the rainy season
C
in the absence of light
D
when the temperature is high
Question 16
Plant cooling occurs due to
A
guttation
B
assimilation
C
transpiration
D
photosynthesis
Question 17
Which of the following is a macronutrient?
A
Ca
B
Cu
C
Mn
D
Zn
Question 18
Premature leaf fall is due to the deficiency of
A
phosphorus
B
potassium
C
sodium
D
zinc
Question 19
Stomata usually open because they have
A
thin guard cells
B
bean-shaped structure
C
high concentration of CO2
D
low concentration of CO2
Question 20
Which of the following are not micronutrients?
A
P, Mg
B
Cu, B
C
Mo, Zn
D
Mn, Cu
Answers
Answer:
q.no.15 ans (d) because of high temperature it release water through the process called transpiration
10. Guard cells help in
A . guttation
B . transpiration ✔
C . protection against grazing
D . fighting against infection
Option B: Guard cells are the two kidney shaped cells that protect the stomata. They play an important role in the process of transpiration, a process by which excessive water is released by the plants to the atmosphere.
11. Which of the following is NOT an essential micronutrient?
A . Boron
B . Calcium ✔
C . Manganese
D . Nickel
Option B: Calcium is a macronutrient required by plants, that is, plants need this nutrient and large amounts.
12. Deficiency of molybdenum causes:
A . chlorosis of leaves
B . bending of leaf tip
C . poor development of vascular system
D . mottling and necrosis of leaves ✔
Option D: Molybdenum is a micronutrient but its deficiency in plants cause mottling and scalding in leaves.
13. What are micronutrients?
A . They are as important in nutrition as the macronutrients. ✔
B . They are more important in nutrition than macronutrients.
C . They may be omitted from culture media without any detrimental effect on the plant.
D . They are called ‘micro’ because they play only a minor role in plant nutrition.
Option A: Micronutrients are as important as macronutrients in plant nutrition. Even though they are only required in very small amounts, their deficiency can prove to be hazardous to plants.
14. The leaves become yellow due to the deficiency of
A . iron and magnesium ✔
B . potassium and calcium
C . nitrogen and copper
D . zinc and boron
Option A: Iron and magnesium deficiency in plants can lead to development of yellow leaves.
15. Rate of transpiration increases
A . in water
B . in the rainy season
C . in the absence of light
D . when the temperature is high ✔
Option D: The process of transpiration accelerates with the atmospheric temperature is high. This is because sunlight accelerates the process of water evaporation from stomata.
16. Plant cooling occurs due to
A . guttation
B . assimilation
C . transpiration ✔
D . photosynthesis
Option C: Transpiration process in plants is similar to the sweating process in human beings. When excessive water content is expelled from plants, it creates a cooling effect.
17. Which of the following is a macronutrient?
A. Ca ✔
B. Cu
C. Mn
D. Zn
Option A: Calcium (Ca) is a macronutrient essential for plants. Its deficiency can cause growth issues in plants.
18. Premature leaf fall is due to the deficiency of
A . phosphorus ✔
B . potassium
C . sodium
D . zinc
Option A: The deficiency of phosphorus nutrient in plants can cause premature leaf fall.
19. Stomata usually open because they have
A . thin guard cells
B . bean-shaped structure
C . high concentration of CO2
D . low concentration of CO2 ✔
Option D: High concentration of CO2 in guard cells cause them to close the stomata. This means that stomata usually open when there is a low concentration of CO2.
20. Which of the following are not micronutrients?
A . P, Mg ✔
B . Cu, B
C . Mo, Zn
D . Mn, Cu
Option A: Phosphorus (P) and Magnesium (Mg) are the two macronutrients while the rest are micronutrients.