ch. 11 vocab

Pericardium

Membrane enclosing the heart, consisting of an outer fibrous layer and an inner double layer of serous membrane.

Atria (atrium)

Each of the two upper cavities of the heart from which blood is passed to the ventricles.

Ventricles

A hollow part or cavity in an organ.

Septa

A dividing wall or membrane especially between bodily spaces or masses of soft tissue.

Fossa ovalis

A depression in the right atrium of the heart, at the level of the interatrial septum.

AV valves

Valves located between the atria (upper chambers) and ventricles (lower chambers).

Chordae tendineae

Fibrous strands in the heart that connect the AV valves to the papillary muscles in the ventricles.

Systemic circulation

The pathway of blood flow that supplies blood to all parts of the body except the lungs.

Pulmonary circulation

Part of the cardiovascular system that carries blood between the heart and lungs.

Coronary circulation

The system of blood vessels that supply the heart muscle (myocardium) with oxygen and nutrients, and then drain away the deoxygenated blood.

Coronary vessels

Blood vessels that supply the heart muscle with oxygen and nutrients.

Sinoatrial node

The heart's natural pacemaker, located in the upper right atrium near the superior vena cava.

Systole

The phase of the heartbeat when the heart muscle contracts and pumps blood out of the chambers.

Diastole

Phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.

Cardiac cycle

The sequence of events that occur during one complete heartbeat, from the start of one beat to the start of the next.

Cardiac output

The amount of blood the heart pumps in 1 minute.

Heart rate

Number of times the heart beats per minute.

Stroke volume

The amount of blood pumped out of the left ventricle with each heartbeat.

Arteries

Blood vessels that carry blood away from the heart.

Renal artery

Major blood vessel that supplies oxygenated blood to the kidneys.

Arterioles

Small blood vessels that branch off from arteries and lead to capillaries, forming part of the microcirculation.

Capillary beds

Network of small blood vessels that allow the exchange of gas, water, and nutrients.

Venules

Very small veins, especially ones collecting blood from the capillaries.

Veins

Blood vessels that carry blood to the heart from tissues and organs in the body.

Hepatic portal system

Unique circulatory system that connects two systems of capillary beds: one in the liver and the other in the wall of the small intestine and spleen.

Vital signs

Measurable physiological indicators that reflect a person's overall health and well-being.

Pulse

Regular movement of blood through the body that is caused by the beating of the heart.

Pressure points

Specific locations on the body where an artery runs close to the surface and can be compressed against an underlying bone to control blood flow.

Systolic pressure

Maximum force exerted by blood against the arteries when the heart contracts and pumps blood throughout the body.

Diastolic pressure

The bottom number in a blood pressure reading, representing the minimum pressure in the arteries between heartbeats when the heart is relaxed.

Peripheral resistance

The resistance in the circulatory system that is used to create blood pressure, affecting blood flow and cardiac function.

Vasoconstriction

The narrowing of blood vessels, typically due to the contraction of the smooth muscles within the vessel walls.

Hypotension

Low blood pressure, happens when blood pressure drops below the normal range, typically below 90/60 mm Hg.

Hypertension

A condition where the force of blood pushing against artery walls is consistently too high.