Auxin can be bioassayed by

1. Avena coleoptile curvature

2. hydroponics

3. potometer

4. lettuce hypocotyl elongation

What causes a green plant exposed to the light on only one side, to bend toward the

source of light as it grows?

1. Green plants need light to perform photosynthesis

2. Green plants seek light because they are phototropic

3. Light stimulates plant cells on the lighted side to grow faster

4. Auxin accumulates on the shaded side, stimulating greater cell elongation there

Dr. F Went noted that if coleoptile tips were removed and placed on agar for one hour, the agar would produce a bending when placed on one side of freshly cut coleoptile stumps. Of what significance is this experiment?

1. It made possible the isolation and exact identification of auxin.

2. It is the basis for quantitative determination of small amounts of growth-promoting substances

3. It demonstrated polar movement of auxins

4. It supports the hypothesis that IAA is auxin

A few normal seedlings of tomato were kept in a dark room. After a few days they were

found to have become white-coloured like albinos. Which of the following terms will you

use to describe them?

1. Mutated

2. Embolised

3. Etiolated

4. Defoliated

Which one of the following growth regulators is known as "stress hormone" ?

1. abscisic acid

2. Ethylene

3. GA₃             

4. lndole acetic acid

During seed germination its stored food is mobilised by.

1. ethylene
2. cytokinin
3. ABA
4. gibberellin

Phototropic curvature is the result of uneven distribution of.

1. gibberellin

2. phytochrome

3. cytokinins

4. auxin

Photoperiodism was first characterised in :-

1. tobacco

2. potato

3. tomato 

4. cotton

Coiling of garden pea tendrils around any support is an example of 
1. thigmotaxis
2. thigmonasty 
3. thigmotropism
4. thermotaxis

One of the synthetic auxin is 

1. NAA

2. IAA

3. GA

4. IBA