GlossariesGCSE GlossariesGCSE Biology GlossaryCapillaries

Capillaries - GCSE Biology Definition

Reviewed by: Lára Marie McIvor

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Capillaries are the smallest blood vessels in the human body and are essential for the exchange of substances between the blood and body tissues. They connect arteries to veins and have walls that are only one cell thick, allowing oxygen and nutrients to diffuse out of the blood into cells, and waste products like carbon dioxide to diffuse from cells into the blood. This exchange is vital for maintaining healthy tissue function and supports the overall efficiency of the circulatory system.

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Lára Marie McIvor

Reviewer: Lára Marie McIvor

Expertise: Biology, Psychology & Sociology Subject Lead

Lára graduated from Oxford University in Biological Sciences and has now been a science tutor working in the UK for several years. Lára has a particular interest in the area of infectious disease and epidemiology, and enjoys creating original educational materials that develop confidence and facilitate learning.

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