Cardiovascular System Notes

Vocabulary flashcards covering key concepts related to the cardiovascular system, including definitions of terms and functions associated with the heart.

Erythropoietin

A hormone made by the kidneys that stimulates the production of red blood cells.

Renin

An enzyme produced by the kidneys that regulates blood pressure and fluid balance.

Systole

The phase of the heartbeat when the heart muscles contract and pump blood.

Diastole

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

Heart Block

A condition in which the electrical signals in the heart are disrupted, affecting heart rhythm.

Heart Sounds

Sounds produced by the closure of heart valves; commonly referred to as 'lub' (first sound) and 'dub' (second sound).

First Heart Sound (S1)

Caused by the closure of the atrioventricular (AV) valves.

Second Heart Sound (S2)

Caused by the closure of the semilunar valves.

Heart Murmurs

Abnormal heart sounds that may be normal in children or indicate a problem in adults, often caused by valve disorders.

Thrombin

An enzyme that converts fibrinogen into fibrin in the clotting process.

Fibrinogen

A soluble plasma protein that is converted into fibrin by thrombin during blood clotting.

Intercalated Disks

Specialized connections between cardiac muscle cells that facilitate electrical impulses and coordinated contraction.

Gap Junctions

Communicating junctions between cells that allow ions and small molecules to pass directly from one cell to another, critical for synchronized cardiac contraction.