Photoperiodism

Q.

Phytochrome is involved in

1. Geotropism

2. Photorespiration

3. Phototropism

4. Photoperiodism

Q. Circadian rhythms are

1. daily (24 Hr) rhythms
2. monthly rhythms
3. annual rhythms
4. seasonal rhythms

Q. Assertion: Chrysanthemum is flashed with 660 nm of light, the flower does not bloom even if the light period is well below the critical photoperiod. Reason: Chrysanthemum is a long-day flowering plant.

1. Both assertion and reason are correct statements and reason is the correct explanation to the assertion
2. Both assertion and reason are correct statements and reason is an incorrect explanation to the assertion
3. Only assertion is correct
4. Both assertion and reason are incorrect

Q.

is the chloroplasts in c3 plants dimorphic?

Q.

Which pigment is involved in photoperiodic change in plants?

1. Phytochrome

2. Cytochrome

3. Chlorophyll

4. Anthocyanin

Q. The minimum length of the day or photoperiod required to induce flowering in a plant is called its .

1. photoperiodism
2. critical day length
3. vernalisation
4. critical dark length

Q. Certain pigments regulate the process of photoperiodism. The pigments exist in two photochemically inter-convertible forms, operating at two different wavelength of light.
The pigments in question are the:

1. Carotenoids
2. Xanthophylls
3. Phytochromes
4. Chlorophylls

Q. The response of plants to the changing duration of light and dark periods is termed as .

1. phototropism
2. photoperiodism
3. heliotropism
4. dormancy