Circulatory System Flashcards

Vocabulary flashcards for the circulatory system, covering key terms and definitions from the lecture notes.

Circulatory System

The system that moves blood throughout the body, carrying nutrients and oxygen to cells and removing waste products.

Arteries

Blood vessels that carry blood away from the heart. They have thick walls and do not contain valves.

Arterioles

Smaller vessels that receive blood from the arteries.

Vasoconstriction

Contraction of smooth muscle in arterioles, reducing the diameter of the blood vessels and decreasing blood flow to tissues.

Vasodilation

Dilation (widening) of arterioles, increasing blood flow to the tissues.

Atherosclerosis

Degeneration of blood vessels caused by the accumulation of fat deposits in the inner wall.

Arteriosclerosis

A group of disorders that cause blood vessels to thicken, harden, and lose elasticity.

Aneurysm

A bulge in the wall of a weakened blood vessel.

Cardiac catheterization

A procedure where a thin tube (catheter) is threaded through a vessel to the heart to analyze blockage.

Angioplasty

A procedure where a balloon is placed inside a vessel and inflated to compress plaque and open up the vessel.

Capillaries

The tiniest blood vessels, composed of a single layer of cells, where fluid and gas exchange occurs between blood and body cells.

Bruising

The internal bleeding of blood coming from a ruptured capillary bed that is visible under the skin.

Venules

Larger vessels formed when capillaries merge, containing smooth muscle in their walls.

Veins

Vessels formed when venules merge, having larger diameters and containing one-way valves to facilitate blood flow back to the heart.

Aorta

The largest artery in the body that carries oxygenated blood from the heart to the body.

Superior and Inferior Vena Cava

Carry deoxygenated blood from the body and empty into the right atrium of the heart.

Pulmonary circulatory system

Vessels that pumps blood to and from the lungs.

Systemic circulatory system

Vessels that carry blood to and from the body tissues.

Pulmonary arteries

Carry deoxygenated blood away from the heart.

Pulmonary veins

Carry oxygenated blood to the heart.

Atria

Thin-walled chambers of the heart that receive blood from veins.

Ventricles

Thick-walled chambers of the heart that pump blood to the arteries.

Atrioventricular (AV) valves

Valves that separate the atria from the ventricles, preventing blood backflow into the atria.

Semilunar valves

Valves that separate the ventricles from the arteries (pulmonary artery and aorta), preventing blood backflow into the ventricles.

Diastole

Heart relaxes, atria fill with blood. AV valves are open so when the atria contract, the ventricles fill with blood. Semilunar valves are closed.

Systole

Ventricles contract to pump blood out of the heart. AV valves are closed. Semilunar valves are open so blood can leave the heart.

SA (sinoatrial) node

A bundle of specialized nerve and muscles located in the upper right atrium that sets the heart rate; the pacemaker.

Stroke volume

The volume of blood that is pumped out of the heart with each heartbeat.

Heart rate

How many times the heart beats every minute.

Cardiac output

The total amount of blood pumped out of the heart every minute, calculated by multiplying stroke volume and heart rate.

Blood pressure

The force of the blood on the walls of the arteries.

Systolic pressure

The higher pressure reading when ventricles contract.

Diastolic pressure

The pressure in the arteries when the blood is filling up the ventricles of the heart.

Medulla oblongata

The blood pressure regulator in the brainstem.

Adrenaline (epinephrine)

The hormone released by the adrenal glands during times of stress.

Extracellular Fluid (ECF)

The fluid that occupies the spaces between cells and tissues.

Filtration

Water moves from an area of higher pressure inside the capillary to lower pressure in the ECF.

Absorption

Osmotic pressure draws water back into the capillary because the concentration of water is greater in the ECF so water moves into the capillary.

Hemorrhage

Excessive bleeding.

Edema

Tissue swelling.

Lymph

A fluid similar to blood plasma.