Opening and Closing of the Stomata

Q.

Which of the following facilitates opening of stomatal aperture?

1. Contraction of outer wall of guard cells

2. Decrease in turgidity of guard cells

3. Radial orientation of cellulose microfibrils in the cell wall of guard cells

4. Longitudinal orientation of cellulose microfibrils in the cell wall of guard cells

Q. Assertion: Opening and closing of stomata is controlled by guard cells.
Reason: Shrinking of guard cells results in the opening of stomatal pore.

1. Only assertion is wrong.
2. Only reason is wrong.
3. Both assertion and reason are wrong.
4. Both assertion and reason are true.

Q.

Both apoplast pathway and symplast pathway occurs according to the water potential gradient.

1. False

2. True

Q.

Are nutrients absorbed by plant leaves?

Q.

" The rate of photosynthesis increases with increase in intensity of sunlight till 0.02 % CO2 level and further increases with increase in intensity of sunlight only if CO2 level rises to 0.05%, " As per the video lesson and our book . But increase in CO2 level above 0.02% causes stomatal closure, which should reduce the rate of exchange of gases causing decrease in the rate of photosynthesis. Then why it's opposite happens?

Q.

Which of the following is true about stomata?

1. All the above

2. Their main function is to allow gases into and out of the leaf.

3. They are found on the epidermis.

4. They consist of two specialized cells- guard cells and stoma.

Q.

Where is ATP made in bacteria?

Q.

Give biological reason for the following:

Tensile strength of water.

Q. Sort the activities happening inside the guard cell leading to the opening of stomata.

1. Pump in K+ ions
2. Tonicity rises
3. Water flows in
4. Turgidity
5. Stomata opens

Q.

Foliar transpiration includes _______.

1. Lenticular transpiration.

2. Stomatal transpiration

3. Cuticular transpiration

4. Both a & b

Q. Why does the sugar present in guard cells turn into starch at night??????

Q. Active K${}^{+}$ mechanism of opening and closing of the stomata was given by

1. Leuitt
2. Scarth
3. Khorana
4. Darwin

Q.

One of the internal factors which affect the rate of transpiration is

Q.

The CO₂ present in the atmosphere enters the stomata by ____.

Q. Assertion (A) The imbalance in the concentration of $N{a}^{+},K^{+}$ and proteins generates resting potential.
Reason (R) To maintain the unequal distribution of $N{a}^{+}$ and $K^{+}$, the neurons use electrical energy.

1. Both A and R are correct and R is the correct explanation of A
2. Both A and R are correct, but R is not the correct explanation of A
3. A is correct, but R is incorrect
4. Both A and R are incorrect

Q.

State whether True or False.

During the daytime, the guard cells begin photosynthesis and the glucose produced during the process increases the osmotic pressure which draws water from the adjoining cells due to endosmosis.

1. True

2. False

Q. Is the stomata open at night ...to take in oxygen?

Q.

Which of the below methods are related to the closing of stomata?

1. Exosmosis

2. Endosmosis

3. Diffusion

4. Plasmolysis

Q.

Fill in the blanks:

Force of capillarity does not operates in plants because xylem of root _________ dip in soil water.

Q.

During the day, chloroplasts in the guard cells photosynthesise, which leads to the production of ___. This is used to actively pump the ___ ions of the adjacent cells into the guard cells.

1. ATP, water

2. ADP, water

3. ADP, potassium ions

4. ATP, potassium ions

Q.

The amount of transpiration from lenticels is lesser than the cuticular transpiration.

1. False

2. True

Q.

Water vapor exits and $C{O}_2$ enters a leaf through the

1. porphyrin rings

2. photons

3. stomata

4. grana

Q. Choose the correct option from the following.

1. The opening and closing of stomatal pores are regulated by guard cells by increasing or decreasing the amount of water in them.
2. Cells shrink when they are placed in a hypotonic solution.
3. Cells swell when they are placed in an isotonic solution.

1. Only statements 2 and 3 are correct.
2. None of the statements are correct.
3. All of the statements are correct.
4. Only statement 1 is correct.

Q.

what is light-dependent reaction??

Q. Stomata open when guard cells swell due to

1. Decreased water potential
2. Increased water potential
3. Endosmosis by efflux of $K^{+}$ ions
4. Endosmosis by influx of hydrogen ions

Q. Sunken stomata

1. Increase transpiration
2. Decrease transpiration
3. Hinder transpiration
4. Stop transpiration

Q.

What is the function of stomata?

Q. The most abundant intracellular cation is

1. $C{a}^{++}$.
2. $H^{+}$.
3. $N{a}^{+}$.
4. $K^{+}$.

Q. Three cellular processes are listed. Choose the correct combination of processes that involves proton gradient across the membrane.
i) Photosynthesis
ii) Aerobic respiration
iii) Anaerobic respiration

1. i) and ii)
2. i), ii) and iii)
3. ii) and iii)
4. i) and iii)

Q.

stomatal pores are open , when the guard cells ________ ?