chapter 22 Blood Vessels and Circulation

These flashcards cover the anatomy and physiology of blood vessels and their roles in circulation as discussed in the lecture.

Arteries

Blood vessels that carry blood away from the heart.

Veins

Blood vessels that return blood to the heart.

Capillaries

Thin-walled vessels where exchange of nutrients and gases occurs.

Adventitia

The outer layer of blood vessel walls, made of connective tissue.

Media

The middle layer of blood vessel walls, primarily composed of smooth muscle.

Intima

The inner layer of blood vessel walls, including endothelial lining.

Vasoconstriction

The process where blood vessels narrow due to smooth muscle contraction.

Vasodilation

The process where blood vessels widen due to smooth muscle relaxation.

Lumen

The internal space of a blood vessel.

Elastic arteries

Large arteries that contain a lot of elastic tissue.

Muscular arteries

Arteries that transport blood to skeletal muscles and internal organs.

Arterioles

Small blood vessels that regulate blood flow from arteries to capillaries.

Continuous capillaries

The most common type of capillaries with a complete endothelial lining.

Fenestrated capillaries

Capillaries with pores allowing for greater permeability.

Sinusoids

Irregularly shaped capillaries with large gaps for filtering.

Precapillary sphincters

Smooth muscle rings that regulate blood flow into capillaries.

Anastomoses

Connections between arteries and veins that reduce blockage impact.

Venoconstriction

Contraction of smooth muscle in veins to squeeze blood into the arterial system.

Capacitance vessels

Veins that can stretch and hold more blood, acting as reservoirs.

Skeletal muscle pump

Mechanism where muscle contractions help move blood in veins.

Hepatic portal vein

Vein that carries nutrient-rich blood from the intestines to the liver.

Umbilical arteries

Blood vessels that carry deoxygenated blood from the fetus to the placenta.

Umbilical vein

Blood vessel carrying oxygenated blood from the placenta to the fetus.

Foramen ovale

An opening in the fetal heart that allows blood to bypass the lungs.

Ductus arteriosus

A fetal blood vessel that connects the pulmonary trunk to the aorta.

Thrombus

A stationary blood clot formed within a blood vessel.

Embolism

A blood clot that travels and lodges in a small artery.

Aneurysm

An abnormal bulge in a blood vessel wall that can potentially rupture.

Nutrient exchange

The process occurring in capillaries where nutrients and gases are exchanged.

Collaterals

Alternative pathways for blood flow if the main vessel is blocked.

Blood reservoirs

Veins that store excess blood that can be mobilized when needed.

Ductus venosus

A shunt in fetal circulation allowing blood to bypass the liver.

Inferior vena cava

Large vein that carries deoxygenated blood from the lower body to the heart.