Phytohormones and Auxin Lecture Review

This set of flashcards covers key concepts related to phytohormones, particularly auxin, its interactions, and experimental observations in plant physiology.

What are phytohormones?

Chemical messengers that coordinate the activity of certain plant organs.

What is auxin's primary function in plants?

Auxin regulates plant growth by influencing cellular activities such as division, elongation, and differentiation.

Give an example of a main phytohormone.

Auxin, Cytokinin, Gibberellins, etc.

What effect do auxins have on shoot and root branching?

Auxins inhibit branching in the shoot and promote branching in the root.

How do cytokinin and auxin interact?

Cytokinins act antagonistically to auxins, inhibiting shoot branching while promoting root branching.

What role do strigolactones play in plants?

Strigolactones inhibit branch outgrowth and attract mycorrhizal fungi.

What are gibberellins known to promote?

Gibberellins promote growth, seed germination, flowering, and fruit growth.

What happens when phytohormone synthesis or response is disrupted?

It interferes with plant growth and elongation.

How do auxin and cytokinin regulate each other at the root apex?

Through mutual regulation of synthesis, transport, and response, they coordinate cellular activities.

What experimental setup was used in phototropism studies?

Mica sheets were used to block auxin flow, showing its role in bending towards light.