Circulatory and Gas Exchange System Keywords

When the heart muscle is relaxed and the atria of the heart, and then the ventricles are filling with blood. 

The muscular wall of the atria contracts. This pushes the blood from the atria into the ventriles, so that the atria are now emptied. This pushes the atrio-ventricular valves fully open. 

The muscular walls of the ventricles contract. The atrio-ventricular valves are forced shut. They can only open one way this works accordingly due to the pressure. 

Stimulates by itself 

Is used to monitor heart function. 

There is no P wave and no QRS wave, this is because the muscle in the heart wall is not contracting in a coordinated way: likely that this person has had a heart attack and is certain to be unconscious and needs urgent medical attention or he will die. 

Small and unclear P wave, deep S wave in 3d indicates ventricular hypertrophy which is an increase in muscle thickness. 

The volume of blood pumped out of the left ventricle in one cardiac cycle. Normally 60-80cm3. 

Is the volume of blood pumped out of the left ventricle in one minute. This figure is normally 4-8dm3min-1. 

Cardiac output = stroke volume x heart rate 

Is when everything is moving in a stream in one direction. 

Blood stays in vessels at all times unless injured. 

High blood pressure: 140/90mmHg

Low blood pressure 90/60mmHg

120/80mmHg

A group of similar cells specialised to carry out the same function. 

Breathe in -> trachea -> two bronchi -> bronchioles -> alveoli

Is a lining tissue of flattened cells. 

Is a structure made up of different kinds of tissue. 

Liquid lining the lungs stops them from sticking together and makes it easier to inflates also has an antibacterial effect. 

The volume of air breathed in and out with a normal breathe, normally around 0.5dm3.

When you breathe out as much air as possible and the breathe out as much air as possible normally about 3.5dm3

When you breathe out as much as you can the small amount left that prevents your lungs from sticking together normally about 1.5dm3

An apparatus that can be used to measure lung volumes. 

The volume of air that can be breathed out in the first second of forced breathing out. 

The maximum rate at which air can be forcibly breathed out through the mouth. 

When a person stops breathing but their heart still beats