Starch is converted to malic acid (organic acid) through the action of an enzyme phosphoenol pyruvate carboxylase (PEPC) under condition of high pH when most of the CO₂ is utilized due to high photosynthetic rate during daytime.

Correct Option: A

Starch is converted to malic acid (organic acid) through the action of an enzyme phosphoenol pyruvate carboxylase (PEPC) under condition of high pH when most of the CO₂ is utilized due to high photosynthetic rate during daytime.

Transpiration is responsible for saturation of the atmosphere.

Correct Option: B

Transpiration is responsible for saturation of the atmosphere.

Potometer is an apparatus used for measuring the rate of transpiration.

Correct Option: B

Potometer is an apparatus used for measuring the rate of transpiration.

Translocation of organic solutes occur through sieve tubes in the form of sucrose. Transportable form of sugar is sucrose.

Correct Option: D

Translocation of organic solutes occur through sieve tubes in the form of sucrose. Transportable form of sugar is sucrose.

During scarcity of water in the soil, stress hormone abscisic acid is produced which brings about stomatal closure. ABA inhibits the uptake of K⁺ by the guard cells and promotes leakage of malic acid from guard cell. This results in loss of water from guard cell due to its lower osmotic potential. Guard cell becomes flaccid leading to closure of stomatal aperture. ABA also causes stomatal closure under high concentration of CO₂ in the guard cells.

Correct Option: B

During scarcity of water in the soil, stress hormone abscisic acid is produced which brings about stomatal closure. ABA inhibits the uptake of K⁺ by the guard cells and promotes leakage of malic acid from guard cell. This results in loss of water from guard cell due to its lower osmotic potential. Guard cell becomes flaccid leading to closure of stomatal aperture. ABA also causes stomatal closure under high concentration of CO₂ in the guard cells.