Blood Vessels and Circulation Study Guide

These flashcards cover essential vocabulary and concepts from the blood vessels and circulation lecture, giving a thorough overview of the cardiovascular system.

Arteries

Blood vessels that carry blood away from the heart.

Veins

Blood vessels that carry blood back toward the heart.

Capillaries

Microvessels that connect arterioles and venules; the primary site of exchange for gases, nutrients, and wastes.

Tunica interna (intima)

The innermost layer of a blood vessel, consisting of endothelium that is selectively permeable and repels blood cells/platelets.

Tunica media

The middle layer of blood vessels, made of smooth muscle and elastic tissue, responsible for vasoconstriction and vasodilation.

Tunica externa (adventitia)

The outer layer of blood vessels, made of connective tissue, that anchors vessels and contains vasa vasorum.

Conducting arteries

Also known as elastic arteries; examples include the aorta and pulmonary trunk, which expand during systole and recoil during diastole.

Resistance arteries

Small arteries and arterioles that control blood flow into organs.

Aneurysm

A bulging sac formed by the weakening of an arterial wall.

Capillary beds

Networks of capillaries that are controlled by precapillary sphincters, providing perfusion.

Venous valves

Structures in veins that prevent backflow of blood.

Peripheral resistance

Resistance in the blood vessels that affects blood flow; depends on viscosity, vessel length, and vessel radius.

Blood Pressure

The force exerted by circulating blood upon the walls of blood vessels, measured at the brachial artery.

Hydrostatic pressure

The pressure exerted by a fluid due to gravity; in capillary exchange, it pushes fluids out.

Colloid osmotic pressure

The pressure that pulls fluids in, related to proteins like albumin in blood.

Edema

Swelling caused by excess fluid trapped in the body's tissues, often due to increased filtration or decreased reabsorption.

Venous return

The flow of blood back to the heart, facilitated by several mechanisms including skeletal muscle pump and thoracic pump.

Circulatory shock

A life-threatening condition of inadequate blood flow to the organs, which can be classified into several types.

Hepatic Portal System

A system of veins that carry nutrients from the GI tract to the liver for processing.

Hypertension

High blood pressure, often referred to as a silent killer, associated with various health risks.