Circulatory System

Circulatory System Function

Transports oxygen, nutrients, and other substances throughout the body, and removes wastes from tissues.

Myocardium

The muscle layer of the heart that contracts to pump blood.

Atrium

An upper chamber of the heart that receives blood from the body.

Ventricle

A lower chamber of the heart that pumps blood out of the heart.

Septum

A wall that separates the right and left sides of the heart to prevent oxygen-poor and oxygen-rich blood from mixing.

Coronary Arteries

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

Pulmonary Circulation

The pathway of blood from the right side of the heart to the lungs.

Systemic Circulation

The pathway of blood from the left side of the heart to the rest of the body.

Sinoatrial Node (SA Node)

The pacemaker of the heart located in the right atrium that sets the pace for heartbeats.

Atrioventricular Node (AV Node)

A node that receives impulses from the SA node and spreads them to the ventricles.

Blood Vessels

Three types of vessels (arteries, capillaries, veins) through which blood flows in the circulatory system.

Arteries

Large vessels that carry oxygen-rich blood from the heart to the body tissues.

Capillaries

The smallest blood vessels where the exchange of blood, nutrients, and waste occurs.

Veins

Vessels that return oxygen-poor blood back to the heart.

Blood Pressure

The pressure exerted by circulating blood upon the walls of blood vessels.

Heart Rate

The number of beats per minute, varying based on the body's oxygen needs.

Neurotransmitters

Chemicals released by the nervous system that influence heart rate.

Blood Oxygen Exchange

The process where carbon dioxide diffuses from the blood and oxygen is absorbed in the lungs.

Valves

Connective tissue flaps located between the atria and ventricles that ensure one directional blood flow.

Elasticity of Arterial Walls

The ability of arteries to stretch and rebound, helping to maintain blood pressure.