The Human Heart and Circulatory System

Vocabulary-style flashcards covering the anatomy, muscular features, and blood flow pathways of the human heart based on lecture notes.

Heart

A muscular organ responsible for pumping blood throughout the body by repeated cyclic contractions.

Atria

Chambers of the heart that receive blood and fill up.

Ventricles

Chambers of the heart that pump blood out and empty.

Septum

The muscular wall that separates the two sides of the heart.

Right side of the heart

Contains oxygen-poor blood with $CO_2$.

Left side of the heart

Contains oxygen-rich blood with $O_2$; features more muscular walls to squeeze blood into the aorta.

Valves

Thin flaps of tissue that ensure blood flows in one direction and create the "LUB-DUB" heartbeat sound when closing shut.

Pericardium

A tough double membrane which surrounds the heart.

Cardiac Muscles

Muscular walls of the heart that repeatedly contract with very little relaxation and are able to remove toxic wastes easily.

Pacemaker Cells

Nerve cells found in the cardiac muscle that control the heartbeat by contracting cardiac muscle cells at the same time.

Systemic Circuit

The pathway of vessels that moves blood from the heart to the body tissues and back to the heart, delivering oxygen and removing $CO_2$.

Pulmonary Circuit

The pathway of vessels that moves blood from the heart to the lungs and back to the heart to pick up oxygen and remove $CO_2$.

Total Daily Blood Flow

More than $7000\,L$ of blood moves through the circulatory pathways every day.

Coronary Arteries

Two main arteries on the outside of the heart that receive blood from the aorta to supply the heart muscle with oxygen and nutrients.

Heart Attack

A condition caused by a blocked coronary artery.

Superior Vena Cava

The main vein that drains blood from the head and arms into the heart.

Inferior Vena Cava

The main vein that drains blood from the lower body into the heart.

Right Atrioventricular / Tricuspid Valve

The valve forced shut when the ventricles contract, preventing blood from re-entering the right atrium.

Right Ventricle

The heart chamber with a thinner wall that pumps blood only to the lungs.

Pulmonary Trunk / Pulmonary Artery

The main artery taking deoxygenated blood to the lungs.

Pulmonary Vein

Carries oxygenated blood from the lungs back into the left atrium of the heart.

Left Atrioventricular / Mitral / Bicuspid Valve

The valve through which blood passes to enter the left ventricle.

Left Ventricle

The heart chamber with a thickened wall required to pump blood throughout the whole body.

Aorta

The main artery to the body which branches into other arteries, including the coronary artery.

Arterioles

Small arteries.

Capillaries

The smallest blood vessels where gas exchange occurs.

Venules

The smallest of the veins, formed by joined capillaries.