arteriole

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Understanding the human cardiovascular system

arteriole

anatomy

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June 17, 2026

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Understanding the human cardiovascular system — Understanding the human cardiovascular system The vascular system is a network of arteries, veins, and capillaries that supplies blood to the tissues of the body.

Arterioles are small arteries that play a crucial role in regulating blood flow within the body. They act as control valves, directing blood from larger arteries into networks of microscopic capillaries. The walls of arterioles are primarily composed of a single layer of smooth muscle, allowing them to constrict or dilate. This ability to change diameter, known as vasoconstriction and vasodilation, is essential for controlling blood pressure and ensuring that blood is delivered to tissues and organs where it is most needed. For instance, during exercise, arterioles supplying skeletal muscles widen to increase blood flow.123

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acrocyanosis
…hands caused by spasms in arterioles (small arteries) of the skin. Less commonly, the feet are affected. The fingers or toes are usually cold and sweat copiously. The cause of the condition is unknown. Acrocyanosis is most common in women, particularly in adolescents and those in their 20s. The condition…
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…hands caused by spasms in arterioles (small arteries) of the skin. Less commonly, the feet are affected. The fingers or toes are usually cold and sweat copiously. The cause of the condition is unknown. Acrocyanosis is most common in women, particularly in adolescents and those in their 20s. The condition…
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blood vessel
…their very small branches are arterioles. Very small branches that collect the blood from the various organs and parts are called venules, and they unite to form veins, which return the blood to the heart. Capillaries are minute thin-walled vessels that connect the arterioles and venules; it is through the…
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…their very small branches are arterioles. Very small branches that collect the blood from the various organs and parts are called venules, and they unite to form veins, which return the blood to the heart. Capillaries are minute thin-walled vessels that connect the arterioles and venules; it is through the…
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artery
…of the smallest arteries, or arterioles, is reached. The threadlike arterioles carry blood to networks of microscopic vessels called capillaries, which supply nourishment and oxygen to the tissues and carry away carbon dioxide and other products of metabolism by way of the veins.
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…of the smallest arteries, or arterioles, is reached. The threadlike arterioles carry blood to networks of microscopic vessels called capillaries, which supply nourishment and oxygen to the tissues and carry away carbon dioxide and other products of metabolism by way of the veins.
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renin-angiotensin system
…constriction of small arteries (arterioles), which causes an increase in blood pressure. Angiotensin II further constricts blood vessels through its inhibitory actions on the reuptake into nerve terminals of the hormone norepinephrine.
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…constriction of small arteries (arterioles), which causes an increase in blood pressure. Angiotensin II further constricts blood vessels through its inhibitory actions on the reuptake into nerve terminals of the hormone norepinephrine.
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