Plant Hormones and Reproductive Development

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the role of ABA in seeds?

Promoting germination

Confering desiccation tolerance and inducing dormancy (correct)

Regulating stomatal aperture

Inhibiting embryonic patterning

What is the outcome of loss of function of ABA signaling in seeds?

Induction of dormancy

Inhibition of germination

Seed abortion

Precocious germination (correct)

What is the term for the germination of seeds while still attached to the parent plant?

Dormancy

Seed maturation

Desiccation tolerance

Vivipary (correct)

Which of the following proteins are involved in ABA signaling and essential for seed development and dormancy?

SRK2D/SnRK2.2, SRK2E/SnRK2.6/OST1 and SRK2I/SnRK2.3 Signup and view all the answers

What is the function of ABA in stomatal aperture regulation?

Regulating stomatal aperture Signup and view all the answers

Which of the following is an example of a plant that lacks seed dormancy?

Rhizophora (red mangrove) Signup and view all the answers

Which hormone is involved in the regulation of elongation in the shoot and root of a germinating soybean?

Gibberellin Signup and view all the answers

What is the function of the TIR1 protein in plant hormone signaling pathways?

Receptor for Auxin Signup and view all the answers

What is the effect of disrupting hormone synthesis or response on plant growth?

Reduced elongation and branching Signup and view all the answers

Which of the following hormones is known to act as 'molecular glue' in plant growth and development?

Hormones in general Signup and view all the answers

What is the role of Brassinosteroids in plant growth and development?

Stimulation of cell growth and elongation Signup and view all the answers

What is the effect of Gibberellin biosynthesis mutants on plant growth?

Reduced stem length Signup and view all the answers

What is required for seed germination to occur?

Elimination of ABA and production of GA Signup and view all the answers

Which hormones regulate fruit growth, maturation, and ripening?

GA, ethylene, and auxin Signup and view all the answers

What is the role of ABA in plant responses to stress?

It helps plants respond to stress Signup and view all the answers

What is the outcome of GA and ethylene promoting flowering in some plants?

Increased seed production Signup and view all the answers

What is true about ABA biosynthesis?

It is strongly regulated Signup and view all the answers

Why is understanding hormonal regulation of reproductive development important for food production?

Because most of our caloric intake is derived from seeds Signup and view all the answers

Study Notes

Abscisic Acid (ABA) Functions

ABA accumulates in maturing seeds and is essential for seed dormancy and desiccation tolerance.
ABA synthesis and signaling are required for seed maturation, and its loss of function leads to precocious germination.
ABA regulates stomatal aperture and is involved in embryonic patterning and reserve accumulation.

ABA Signaling Pathway

ABA protein kinase and transcription factors are essential for ABA-induced dormancy.
Three Arabidopsis SnRK2 protein kinases (SRK2D/SnRK2.2, SRK2E/SnRK2.6/OST1, and SRK2I/SnRK2.3) are involved in ABA signaling and are essential for seed development and dormancy.

Hormone Regulation of Plant Growth and Development

Hormones can act like "molecular glue" to facilitate interactions between proteins.
Ion channel regulation involves hormone binding, which initiates an information relay.
Hormones affect vegetative growth, including elongation, branching, and organogenesis.
GA, Auxin, and Brassinosteroids are involved in regulating plant growth and development.

Hormone Regulation of Reproductive Development

GA and ethylene promote flowering in some plants.
Fruit growth, maturation, and ripening are regulated by auxin, GA, and ethylene.
Seed maturation and germination are regulated by ABA and GA.

Hormonal Responses to Abiotic Stress

ABA and ethylene help plants respond to stress, including photooxidative stress, high temperature stress, water deficit, drought, soil salinity, air pollution, wounding, and mechanical damage, and cold and freezing stress.
ABA biosynthesis is strongly regulated, and its levels are tightly controlled to ensure rapid and precise control.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about the role of hormones such as GA, ABA, auxin, and ethylene in plant reproductive development, including seed germination, fruit growth, and flowering. Understand how these hormones regulate plant growth and development.