Plant Responses to Internal and External Signals

These flashcards cover key vocabulary and concepts related to plant responses to environmental signals and internal stimuli as discussed in the lecture.

Gravitropism

The response of plants to gravity; roots exhibit positive gravitropism by growing downward, while shoots exhibit negative gravitropism by growing upward.

Phototropism

The curvature of plant organs in response to light; positive phototropism is when shoots curve toward light, and negative is when roots curve away.

Auxin

A plant hormone that promotes elongation of coleoptiles and is primarily produced in shoot tips.

Ethylene

A plant hormone produced in response to stressors such as drought and flooding, playing a key role in fruit ripening and leaf abscission.

Cytokinins

Plant hormones that stimulate cell division and differentiation, as well as inhibit the growth of axillary buds.

Gibberellins

Plant hormones that promote stem elongation, fruit growth, and seed germination.

Abscisic Acid (ABA)

A hormone that promotes seed dormancy and drought tolerance by closing stomata to reduce water loss.

Thigmomorphogenesis

Changes in plant form that occur as a response to mechanical disturbance.

Circadian Rhythms

Biological processes that oscillate with a frequency of about 24 hours, influenced by the day/night cycle.

Photoperiodism

The physiological response of plants to changes in the length of day and night, influencing flowering and other processes.

PAMP-triggered immunity

An innate immune response in plants that is activated by the detection of pathogen-associated molecular patterns.

Effector-triggered immunity

An immune response in plants that occurs when specific proteins (effectors) from pathogens are detected, leading to increased defense mechanisms.