The Circulatory System III: Blood Vessels

Vocabulary flashcards covering key concepts from the lecture on blood vessels in the circulatory system.

Arteries

Efferent vessels carrying blood away from the heart.

Veins

Afferent vessels carrying blood toward the heart.

Capillaries

Microscopic vessels connecting small arteries to small veins.

Tunica interna

Inner layer of blood vessels, consists of simple squamous endothelium.

Tunica media

Middle layer of blood vessels, thick layer with smooth muscle, collagen, and possibly elastin.

Tunica externa

Outer layer of blood vessels, made of loose connective tissue.

Vasa vasorum

Small vessels that supply blood to the larger blood vessels.

Conducting arteries

Largest arteries that absorb pressure and maintain it, e.g., the aorta.

Distributing arteries

Medium-sized arteries that distribute blood to specific organs, e.g., the femoral artery.

Resistance arteries

Smallest arteries with diameters of less than 0.1 mm, including arterioles.

Metarterioles

Short vessels linking arterioles and capillaries.

Baroreceptors

Neurons in elastic arteries that sense blood pressure.

Chemoreceptors

Neurons in blood vessel walls that sense blood chemistry.

Continuous capillary

Capillary type with endothelial cells joined by tight junctions.

Fenestrated capillary

Capillary with filtration pores facilitating exchange.

Sinusoid capillary

Capillary type with irregular, tortuous passages and wide gaps between endothelial cells.

Precapillary sphincters

Smooth muscles that control blood flow into capillaries based on tissue activity.

Capacitance vessels

Veins that contain most of the blood and act as storage.

Postcapillary venules

Type of veins with a diameter of 15 to 20 µm, allowing for exchange.

Ductus arteriosus

Fetal blood vessel that bypasses lung circulation by connecting pulmonary trunk to the aorta.

Foramen ovale

Fetal opening that allows blood to flow from the right atrium to the left atrium.

Aging and diseases of the vascular system

Common issues include arteriosclerosis, atherosclerosis, and orthostatic hypotension.