Blood Vessels and Blood Circulation

A collection of vocabulary flashcards summarizing key terms related to blood vessels, circulation, and hemostasis.

Systemic Circuit

The pathway in which blood flows from the heart to the body and back, delivering oxygen and nutrients while removing waste.

Pulmonary Circuit

The pathway where blood flows from the heart to the lungs and back, allowing for gas exchange (oxygen in, carbon dioxide out).

Tunica Intima

The innermost layer of a blood vessel, consisting of smooth endothelial cells that help reduce friction and promote blood flow.

Tunica Media

The middle layer of a blood vessel, composed of smooth muscle and elastic fibers, allowing for vasoconstriction and vasodilation to regulate blood pressure.

Tunica Externa (Adventitia)

The outermost layer of a blood vessel, made of connective tissue that provides support and anchors the vessel in place.

Capillaries

Microscopic blood vessels with thin walls that allow for the exchange of nutrients, gases, and waste between the blood and body tissues.

Arteries

Blood vessels that carry oxygen-rich blood away from the heart to body tissues (except in the pulmonary circuit, where they carry oxygen-poor blood to the lungs).

Veins

Blood vessels that return oxygen-depleted blood back to the heart (except in the pulmonary circuit, where they bring oxygenated blood from the lungs).

Arterioles

Small branches of arteries that lead into capillary networks; they help regulate blood flow by constricting or dilating.

Venules

Small veins that collect blood from capillaries and channel it into larger veins.

Vasoconstriction

The narrowing of blood vessels due to contraction of the smooth muscle in the tunica media, which increases blood pressure.

Vasodilation

The widening of blood vessels due to relaxation of the smooth muscle in the tunica media, which decreases blood pressure.

Blood Pressure (BP)

The force exerted by circulating blood on the walls of blood vessels, essential for maintaining blood flow throughout the body.

Systolic Pressure

The pressure in the arteries during the contraction of the heart muscle.

Diastolic Pressure

The pressure in the arteries when the heart muscle is resting between beats.

Net Filtration Pressure (NFP)

The net force determining the movement of fluid into or out of capillaries, calculated as the difference between forces promoting filtration and reabsorption.

Hydrostatic Pressure

The pressure exerted by a fluid within a confined space.

Plasma

The liquid component of blood, primarily composed of water, proteins, electrolytes, nutrients, and waste products.

Hemostasis

The process of stopping bleeding, involving blood vessel constriction, platelet plug formation, and blood clotting.

Lactoferrin

An iron-binding glycoprotein found in serum and mucosal secretions that binds iron and has antimicrobial properties.

Transferrin

The main iron transport protein in the bloodstream that binds to iron and transports it to cells.

Ferritin

A protein that stores iron inside cells and releases it when needed.