capillaries

Smallest blood vessels

Capillaries are the tiniest blood vessels in the body, forming networks that connect arteries to veins.

Their walls are thin enough for oxygen, nutrients, and waste to pass through, making them the site of exchange between blood and tissue.

The word extends to any extremely fine tube or passage: capillary action describes how liquid rises in narrow spaces against gravity.

anatomy

arteries

Tubes carrying oxygenated blood

veinsBlood-return tubes
arteriolesSmallest arterial vessels
venulesSmallest vein branches

blood vessels · endothelium · vascular · microcirculation · circulation · perfusion · bloodflow · cardiovascular · red blood cells · plasma

structure

network

Interconnected system

meshInterlocking open weave
webInterwoven filament structure
branchingSplitting into separate directions

microscopic · fine · delicate · permeable · fenestrated · continuous · tubular · lumen · diameter · walls

porosity

wicking

Liquid drawn through fibers

absorptionProcess of taking in
surface tensionCohesive force at liquid interfaces
meniscusCurved liquid surface

pore · sponge · soil · paper · wick · uptake · moisture · tube · rise · draw

Categories

anatomybrain, heart, bones, liver, stomach
Circulatory Systemheart rate, blood, artery, veins, arteries
circulation systemsblood vessels, arteries, veins, heart, aorta
cardiopulmonaryheart rate, lungs, blood pressure, circulation, breathing
blood vesselsarteries, artery, vein, veins, aorta
bloodstreamblood, plasma, red blood cells, white blood cells, platelets

Opposites

blood vessel size

capillariesaorta

Chief arterial trunk

vena cava · pulmonary artery · femoral artery · carotid artery · jugular vein

vessel function in circulation

capillariesarteries

Tubes carrying oxygenated blood

Phrases

broken capillariesDamaged tiny blood vessels

Family

capillary, capillary action

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