Atrial systole - contraction of the heart
Ventricular systole-contraction of ventricles
Diastole- relaxation of the heart.
Electrical activity spreads out of SAN
Pause - All blood into ventricles
AVN- down th the bundle of His/ side of the ventricles
Cardiac output = stroke volume x heart rate
cm bps (beats per second)
- The right side (left on the paper) pumps deoxygenated blood to the lungs.
- The left side(right on the paper) pumps oxygenated to the body
- .Left ventricle is thicker because it needs to pump blood around the body.
- The ventricles are thicker than the atria because the have to force blood out.
- Atrio ventricular (AV valves) - between atria and ventricles. Stops blood flowing back into atria.
- Semi lunar (SL)- between the pulmonary artery/aorta and ventricles. Stops blood flowig back into ventricles after the contract.
Factors that affect the heart
- carbon monoxide reducing the amount of oxygen in the blood
- Nicotine -produces adrenaline-increases the heart rate and raises blood pressure.
-High blood pressure
- can be in the genes
- can be lifestyle -diet/exercise
- blood has to be pumped hard= heart working harder= prone to failure
- full of fatty foods, high levels of salt
- raised blood pressure, heart failure, increase blood cholesterol concentration
Excersise and heart rate
heart rate x stroke volume =cardiac output
Cardiac output can increase when the body increase
- to get oxygen to the muscles faster
- to get glucose to the muscles faster
- to get carbon dioxide away from the muscles.
- to lactate away from the muscles
- to get heat away from the muscles faster.
When the body exercises the ventilation rate and depth increase so that: oxygen can diffuse from the air to the blood faster and carbon dioxide away from the blood faster.