unit 3 botany (copy) (copy)

What is Auxin?

Auxin is a plant hormone that regulates growth processes such as apical dominance, phototropism, and root versus shoot growth.

Cytokinin

A hormone that promotes cell division and growth, influences shoot development, and can delay leaf senescence.

Ethylene

A gaseous plant hormone involved in fruit ripening, leaf abscission, and responses to stress.

Abscisic Acid (ABA)

A stress hormone that promotes dormancy, inhibits growth, and closes stomata in response to environmental stress.

Gibberellin

A growth-promoting hormone that stimulates stem elongation, seed germination, and flowering.

Brassinosteroids

A group of plant hormones that promote growth, protect against environmental stress, and are essential for cell expansion.

Tropism

The growth response of a plant toward or away from a stimulus.

Phototropism

Positive growth response towards light, controlled by auxin distribution.

Gravitropism

Growth response of plants to gravity, with shoots exhibiting negative gravitropism and roots showing positive gravitropism.

Hydrotropism

The growth of plant roots toward moisture.

Thigmotropism

The directional growth response of a plant to mechanical stimuli, often seen in climbing plants.

Nastic Movement

Non-directional growth response of a plant to stimuli, such as the closing of a Venus flytrap.

Circadian Rhythm

The biological clock in plants that regulates metabolic processes in a roughly 24-hour cycle.

Photoperiodism

The response of plants to the length of day or night, affecting flowering and other developmental processes.

Macronutrients

Essential nutrients required by plants in large amounts, including nitrogen, phosphorus, potassium, and magnesium.

Micronutrients

Essential nutrients needed by plants in smaller amounts, such as iron, manganese, and zinc.

Translocation

The movement of organic nutrients, primarily sugars, through the phloem from sources to sinks in a plant.

Transpiration

The process by which water vapor exits the plant through stomata, leading to the uptake of water from roots.

Stomata

Small openings on the surfaces of leaves that regulate gas exchange and transpiration in plants.

Secondary Metabolites

Organic compounds produced by plants that are not directly involved in primary metabolic processes but play roles in defense and attraction.