Question

Through their effect on plant growth regulators, what do the temperature and light control in the plants?

• A. Apical dominance
• B. Flowering
• C. Fruit elongation
• D. Closure of stomata

Answer 1

The correct option is B

Flowering

The correct option is B.

Explanation of the correct option:

1. Plants need certain organic molecules known as plant growth regulators to promote growth, among other things. Additionally, temperature and light have a significant impact on how plants grow, produce food, and flower.
2. Plant growth is impacted by a number of things. Light and temperature are two of the main influences. The plant needs light for photosynthesis, whereas temperature controls things like germination and transpiration. Temperature and light also affect how plant growth hormones function
3. Through the processes of photoperiodism and vernalization, light and temperature, respectively, regulate flowering in plants.
4. Photoperiodism is the term used to describe how plants respond in terms of lengths of light and dark periods. Different angiosperms use photoreceptor proteins like phytochrome and cryptochrome to sense seasonal changes. The detection provides a signal for flowers to bloom.
5. Vernalization, which occurs as a result of the low winter temperatures, gives plants the capacity to bloom in the spring.

Explanation of the incorrect options:

Option A:

1. The longitudinal development of apical structures, such as plant stem tips, is referred to as apical dominance.
2. It is controlled by a hormone called Auxin, Temperature and light have no effect on this.
3. Hence, it is an incorrect option.

Option C:

1. Gibberellins, which are plant growth regulators, are primarily responsible for fruit elongation. The fruit's form is also improved by the gibberellins.
2. Temperature and light have no effect on fruit elongation. Hence it is an incorrect option.

Option D:

1. Abscisic acid, an inhibitor of plant growth hormone, controls stomata closure in the epidermis.
2. Light or temperature has no effect on the closure of stomata.
3. Hence, it is an incorrect option.

Final answer: Therefore, the temperature and light control flowering in plants.