Skip to main content
Basic Technical IVT Commonly tested

Stomatal closure

noun

Pronunciation: /ˈstoʊmətəl ˈkloʊʒər/

The process by which guard cells reduce stomatal aperture in response to water deficit, heat, or other environmental stresses to minimize transpirational water loss. This is a rapid, reversible response controlled by abscisic acid and other signaling molecules.

Plain English

The narrowing or sealing of microscopic pores on leaves to reduce water loss during plant stress.

Etymology & History

Origin languageGreek, English
Rootstoma (mouth) + closure (act of closing)
First recorded use1950s
Usage frequencyVery common

Usage

"Stomatal closure under heat stress reduced photosynthetic carbon assimilation but effectively prevented excessive water loss."

Style guide notes: Capitalize 'Stomatal Closure' only in formal titles; use lowercase in running text.

Also known as

stomatal restriction pore closure guard cell response

Contrasted with

stomatal opening stomatal dilation

Related Terms

Frequently Asked Questions

How quickly does stomatal closure occur in response to stress?

Stomatal closure typically begins within minutes to hours of stress perception, driven by rapid abscisic acid signaling.

What is the trade-off of stomatal closure?

While water conservation increases, carbon dioxide uptake decreases, reducing photosynthesis and plant growth.

Why Test Candidates on This?

Fundamental concept tested in plant physiology, ecology, and agronomy courses worldwide.

Required skill level: Junior

Editors from these organisations have used our services since 1998

Reuters BBC Oxford University Press Penguin Random House Springer Microsoft Suncor Energy United Nations Fisher Investments IBM The Home Depot KODAK CHEVRON