Plant Growth and Development

What is the site of perception of photoperiod necessary for induction of flowering in plants?

1. Shoot apex
2. Leaves
3. Lateral buds
4. Pulvinus

It takes very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?

1. Gibberellin and Abscisic acid
2. Cytokinin and Abscisic acid
3. Auxin and Ethylene
4. Gibberellin and Cytokinin

Fruit and leaf drop at early stages can be prevented by the application of

1. ethylene
2. auxins
3. gibberellic acid
4. cytokinins.

The Avena curvature is used for bioassay of

1. IAA
2. ethylene
3. ABA
4. GA3.

You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?

1. IAA and gibberellin
2. Auxin and cytokinin
3. Auxin and abscisic acid
4. Gibberellin and abscisic acid

Phytochrome is a

1. flavoprotein
2. glycoprotein
3. lipoprotein
4. chromoprotein

Auxin can be bioassayed by

1. potometer
2. lettuce hypocotyl elongation
3. Avena coleoptile curvature
4. hydroponics.

What causes a green plant exposed to the light, on only one side, to bend towards the source of light as it grows?

1. Light stimulates plant cells on the lighted side to grow faster.
2. Auxin accumulates on the shaded side, stimulating greater cell elongation there.
3. Green plants need light to perform photosynthesis.
4. Green plants seek light because they are phototropic.

Typical growth curve in plants is

1. stair-steps shaped
2. parabolic
3. sigmoid
4. linear.

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 supports the hypothesis that IAA is auxin.
4. It demonstrated polar movement of auxins.