뒤로Blood Vessel Structure and Circulation Physiology
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이 집합의 용어 (24)
Tunica intima: inner endothelial layer for smooth blood flow.
Tunica media: middle layer of smooth muscle controlling vessel diameter.
Tunica externa: outer connective tissue providing support and protection.
Provides a smooth lining to reduce friction and allows selective permeability for exchange.
Controls vessel diameter through contraction (vasoconstriction) and relaxation (vasodilation) to regulate blood flow and pressure.
Provides structural support and anchors the vessel to surrounding tissues.
The narrowing of blood vessels due to contraction of the tunica media smooth muscle, reducing blood flow.
The widening of blood vessels due to relaxation of the tunica media smooth muscle, increasing blood flow.
Elastic arteries: large, with many elastic fibers for pressure buffering.
Muscular arteries: medium-sized, with more smooth muscle for vasoconstriction.
Arterioles: small, regulate blood flow into capillaries.
Maintain blood pressure by stretching and recoiling during heartbeats.
Distribute blood to specific body regions and regulate flow via vasoconstriction/dilation.
Network of thin-walled capillaries allowing exchange of gases, nutrients, and wastes between blood and tissues.
Veins have thinner walls, larger lumens, and valves to prevent backflow; arteries have thicker walls and no valves.
Return deoxygenated blood to the heart and act as blood reservoirs.
Provide alternative pathways for blood flow to ensure tissue perfusion if one route is blocked.
The volume of blood moving through a vessel or circulation per unit time.
The force exerted by blood on vessel walls, usually measured in arteries.
The opposition to blood flow caused by vessel diameter, length, and blood viscosity.
Blood flow = Pressure difference / Resistance; flow increases with pressure and decreases with resistance.
Highest in arteries, decreases in capillaries, and lowest in veins.
Cardiac output, blood volume, resistance, vessel elasticity, and blood viscosity.
By neural, hormonal, and renal mechanisms adjusting heart rate, vessel diameter, and blood volume.
Chronic high blood pressure, often >140/90 mmHg, increasing risk of heart disease and stroke.
Often asymptomatic; can cause heart failure, kidney damage, and vascular disease.
A condition where blood flow is insufficient to meet tissue needs, causing organ failure.
Severe blood loss, heart failure, infection (septic shock), or allergic reaction (anaphylactic shock).