Advanced Placement (AP) Biology Practice Exam

What do plant growth regulators affect?

1. The temperature of the soil

2. The movement of water in plants

3. Plant growth

4. The photosynthesis process

The correct answer is: Plant growth

Plant growth regulators, also known as plant hormones, primarily influence various aspects of plant growth and development. These chemical substances are crucial in regulating processes such as cell elongation, root growth, flowering, fruit development, and response to environmental stimuli. By affecting the rate of growth and differentiation of plant cells, these regulators ensure that plants can adapt to their environment, optimize resource use, and engage in processes such as germination, flowering, and fruiting efficiently. The involvement of plant growth regulators in these developmental processes highlights their significance in agricultural practices and plant biology, where manipulating their levels can lead to improved crop yields and plant health.