Question

Choose the correct answer from the alternatives given.
Which of the following statements is not true about photoperiodism?

• A. A short-day plant flowers when the day length is shorter than some critical length
• B. A day-neutral plant flowers according to some form of regulation other than photoperiodism
• C. A long-day plant will flower even when the day period is not long enough if there is a short period of light during the dark period.
• D. Phytochrome form Pfr is converted to Pr in daylight, producing the active form that induces flowering in long-day plants

Answer 1

The correct option is C A long-day plant will flower even when the day period is not long enough if there is a short period of light during the dark period.

Photoperiodism is the development of plants according to the light and dark periods of the day. Photoperiodism is dependent upon photoreceptor proteins, they may be phytochrome or cytochrome. Phytochromes during daylight get activated into Pfr but in the absence of light or in the dark period they convert into their inactivated form pr. These phytochromes help in the growth and development of a plant.

So, the correct option is 'A long-day plant will flower even when the day period is not long enough if there is a short period of light during the dark period'.