Circulatory System Terms: The Heart

Front 1

Heart

Back 1

4 chambered muscle responsible for pumping blood throughout the body

Front 2

Atria

Back 2

The upper chambers of the heart, thin walled

Front 3

Ventricle

Back 3

The lower chambers of the heart, thick muscular walls

Front 4

Myocardium

Back 4

The muscular wall of the heart, responsible for pushing blood to the entire body. The inner surface is lined with endocardium and the outer surface is lined with pericardium

Front 5

Atrioventricular Valves

Back 5

Valve that lies between the atrium and ventricle on each side

Front 6

Mitral Valve

Back 6

Valve that regulates blood flow from the left atrium to the left ventricle (left atrioventricular valve)

Front 7

Tricuspid Valve

Back 7

Valve that regulates the blood from the right atrium to the right ventricle, to prevent back flow into the atrium (right atrioventricular valve)

Front 8

Semilunar Valve

Back 8

valves between the ventricle, that prevent blood from flowing back into the ventricles (aortic and pulmonary )

Front 9

Aortic Valve

Back 9

Located at the exit of the left ventricle, allows blood to be pumped into the aorta as well as prevents blood to flow back into the heart once it enters the aorta.

Front 10

Pulmonary Valve

Back 10

Separates the right ventricle for the pulmonary artery, allows blood collected in the right ventricle to flow to the lungs as well as prevents blood for flowing back to the heart

Front 11

Superior Vena Cava

Back 11

Large vein that receives blood from the upper body and delivers it to the right atrium

Front 12

Inferior Vena Cava

Back 12

Large vein that receives blood from the lower body and delivers it to the right atrium.

Front 13

Systole

Back 13

The contraction of the heart muscle

Front 14

Diastole

Back 14

The relaxation of the heart muscle

Front 15

Sympathetic Nervous System

Back 15

The part of the autonomic nervous system that prepares the body for stress increase heart rate (flight or fight response)

Front 16

Parasympathetic Nervous System

Back 16

Opposes SNS, by returning the body to a normal resting state following stress

Front 17

Sinoatrial Node

Back 17

A bundle of specialized nerves and muscles, located where the superior vena cava enter the right atrium. Controls the rate of the heart by sending signals to the 2 atriums

Front 18

Atrioventricular Node

Back 18

Located at the lower part of the right atrium, near the tricuspid valves. It receives the signals for SN and sets the heart rate accordingly.

Front 19

Purkinje fibres

Back 19

Two large nerve fibres that run through the septum. Responsible for carrying the nerve signals transmitted by the Atrioventricular Nodes

Front 20

Tachycardia

Back 20

Fast heart beat exceeding 100 beats per minute.

Front 21

Bradycardia

Back 21

Slow heart beat, lower than 60 beats per minute.

Front 22

Electrocardiogram

Back 22

Test that measure the electrical activity of the heart. The test will trace how long the electrical wave takes to pass through the heart

Front 23

P Wave

Back 23

The first little hump on the electrocardiogram. Represents the contraction from the atria

Front 24

QRS Complex

Back 24

Usually the most visual and central part of the diagram. Represents the contraction from the ventricles.

Front 25

T Wave

Back 25

The recovery of the heart

Front 26

Systolic Number

Back 26

Pressure of the blood vessels when your heart contracts and pushes blood out (highest pressure)

Front 27

Diastolic Number

Back 27

Pressure of your blood vessels when the heart is at rest between beats (lowest pressure)

Front 28

Sphygmomanometer

Back 28

Measures blood pressure indirectly, finds pressure exerted by blood in the brachial artery

Front 29

Cardiac Output

Back 29

The volume of blood pumped from the heart each minute. An increased output will increase blood pressure

Front 30

Arteriolar Resistance

Back 30

The diameter of the arterioles is regulated by the ir walls. Constriction reduces blood flow, causing higher blood pressure. Dilatation increases blood flow, causing lower blood pressure.