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. What is the significance of this experiment?
 

1.	It made possible the isolation and exact identification of auxin.
2.	It is the basis for the quantitative determination of small amounts of growth-promoting substances.
3.	It supports the hypothesis that IAA is auxin.
4.	It demonstrates the polar movements of auxins.

A few normal seedlings of a 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 the stress hormone?

1. Abscisic acid

2. Ethylene

3. GA₃

4. Indole acetic acid

During seed germination its stored food is mobilized by:

1. Cytokinin

2. ABA

3. Gibberellin

4. Ethylene

Phototropic curvature is the result of uneven distribution of:

1. gibberellin

2. phytochrome

3. cytokinins

4. auxin

Photoperiodism was first characterized 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

Which one of the following acids is a derivative of carotenoids?

1. Indole-butyric acid

2. Indole-3-acetic acid

3. Gibberellic acid

4. Abscisic acid