Question

Which of the following is(are) auxins?

• A. 1-Naphthaleneacetic acid
• B. Indole-3-butyric acid
• C. 2,4-Dichlorophenoxyacetic acid
• D. Indole-3-acetic acid

Hint:

Indole-3-acetic acid (IAA) is the primary auxin in plants that regulates growth, elongation, and differentiation.

Answer 1

The Correct Option is A, B, C, D

Auxins are a class of plant hormones that play a crucial role in coordinating various growth and behavioral processes in the plant's life cycle. They are essential for the regulation of plant growth by influencing cell elongation, root growth, and differentiation.

The question asks us to identify which of the given substances are auxins. Let's evaluate each option:

• 1-Naphthaleneacetic acid (NAA): NAA is a synthetic auxin used predominantly as a growth regulator. It promotes root development and is often used in agriculture and horticulture to encourage plant growth.
• Indole-3-butyric acid (IBA): IBA is a naturally occurring auxin that is involved in root elongation and cell enlargement. It is widely used in plant propagation.
• 2,4-Dichlorophenoxyacetic acid (2,4-D): 2,4-D is a synthetic auxin commonly used as a herbicide. It mimics the natural auxin activity and causes uncontrolled growth, eventually leading to the death of unwanted plants.
• Indole-3-acetic acid (IAA): IAA is the most prominent and naturally predominant auxin in plants. It plays a significant role in virtually all developmental processes, including cell division, elongation, and differentiation.

All the substances listed are recognized as auxins. They either naturally occur in plants or are synthetic compounds that mimic the behavior of natural auxins by inducing similar physiological responses in plants.

Therefore, the correct answer is:

• 1-Naphthaleneacetic acid
• Indole-3-butyric acid
• 2,4-Dichlorophenoxyacetic acid
• Indole-3-acetic acid

Each of these fulfilling roles associated with auxins makes them integral in plant growth and development processes.