The Circulatory System: Blood Vessels and Circulation

These flashcards cover essential vocabulary related to the circulatory system, focusing on blood vessels, pressure regulation, and related medical conditions.

Arteries

Blood vessels that carry blood away from the heart and have thicker muscle walls to withstand greater pressures.

Veins

Blood vessels that carry blood back to the heart, have larger diameters with thinner walls, and operate under low pressure.

Capillaries

The smallest and most numerous blood vessels that connect the smallest arteries to veins, facilitating the exchange of nutrients and wastes.

Systolic Pressure

The peak arterial blood pressure measured during ventricular contraction.

Diastolic Pressure

The minimum arterial blood pressure measured during ventricular relaxation.

Blood Pressure (BP)

The force that blood exerts against the walls of blood vessels.

Pulse Pressure

The difference between systolic and diastolic pressure, an important measure of stress on arteries.

Mean Arterial Pressure (MAP)

An average blood pressure level in the arteries that influences risk of various health issues.

Hypertension

Chronic high blood pressure, defined as resting BP greater than 130/80 mm Hg.

Hypotension

Chronic low resting blood pressure, often due to blood loss, dehydration, or anemia.

Aneurysm

A weak point in an artery or heart wall that can form a bulging sac and may rupture.

Atherosclerosis

Progressive disease characterized by the thickening of the tunica intima due to atheroma formation.

Capillary Exchange

The two-way movement of fluid across capillary walls, essential for nutrient and waste exchange.

Filtration

The process of fluid movement out of capillaries into surrounding tissues, influenced by hydrostatic and osmotic pressures.

Edema

The accumulation of excess fluid in tissue, occurring when filtration exceeds reabsorption.

Circulatory Shock

A state where cardiac output is insufficient to meet the metabolic needs of the body.

Renin-Angiotensin System (RAS)

A hormone system that regulates blood pressure and fluid balance.

Vasomotion

The changing of blood vessel diameter to control blood pressure and flow.

Neural Control

The regulation of blood vessels through central and autonomic nervous system signals, affecting blood flow.

Baroreceptors

Sensory structures that monitor blood pressure and relay information to the brainstem to regulate heart rate.

Chemoreceptors

Cells that detect changes in blood chemistry and help regulate respiration and blood flow.

Myogenic Response

The ability of smooth muscle in blood vessel walls to respond to changes in pressure by contracting or relaxing.

Hemostasis

The process to stop bleeding, which includes vascular spasm, platelet aggregation, and coagulation.

Thrombosis

Abnormal clotting in unbroken blood vessels, potentially leading to embolism.