Gibberllic acid stimulates cell growth of leaves and stem causing their expansion, elongation respectively and leaf fall is controlled by ABA.

Correct Option: A

Gibberllic acid stimulates cell growth of leaves and stem causing their expansion, elongation respectively and leaf fall is controlled by ABA.

Abscisic acid (ABA), also known as abscisin II and dormin, is a plant hormone. It functions in many plant developmental processes, including bud dormancy. Abscisic acid is a derivative of carotenoids. It was called “abscisin II” originally because it was thought to play a major role in abscission of fruits. At about the same time another group was calling it “dormin” because they thought it had a major role in bud dormancy. The name abscisic acid (ABA) was coined as a compromise between the two groups.

Correct Option: C

Abscisic acid (ABA), also known as abscisin II and dormin, is a plant hormone. It functions in many plant developmental processes, including bud dormancy. Abscisic acid is a derivative of carotenoids. It was called “abscisin II” originally because it was thought to play a major role in abscission of fruits. At about the same time another group was calling it “dormin” because they thought it had a major role in bud dormancy. The name abscisic acid (ABA) was coined as a compromise between the two groups.

NAA is a synthetic auxin. Some of the most widely used weed killers are synthetic auxins. Synthetic auxin analogs include 1–naphthaleneacetic acid (NAA), 2, 4-dichlorophenoxy acetic acid (2, 4-D) and 2,4,5-trichlorophenoxy acetic acid (2,4,5- T).

Correct Option: D

NAA is a synthetic auxin. Some of the most widely used weed killers are synthetic auxins. Synthetic auxin analogs include 1–naphthaleneacetic acid (NAA), 2, 4-dichlorophenoxy acetic acid (2, 4-D) and 2,4,5-trichlorophenoxy acetic acid (2,4,5- T).

Phototrophic curvature is the result of uneven distribution of auxin. The experiments conducted by Charles Darwin concluded that the tip of coleoptile of canary grass contain auxin that causes the bending of the entire coleoptile towards the light source.

Correct Option: D

Phototrophic curvature is the result of uneven distribution of auxin. The experiments conducted by Charles Darwin concluded that the tip of coleoptile of canary grass contain auxin that causes the bending of the entire coleoptile towards the light source.

Gibberellins & ABA are antagonistic to each other. ABA counteracts many effects of gibberellins like induction of hydrolases and alpha- amylases in barley seedlings.

Correct Option: C

Gibberellins & ABA are antagonistic to each other. ABA counteracts many effects of gibberellins like induction of hydrolases and alpha- amylases in barley seedlings.