Circulatory System - HEART Flashcards
What is the function of the circulatory system?
To deliver oxygen, nutrient molecules and hormones and to remove Co2 and other wastes
What is the difference between the top and bottom chambers of the heart?
The two chambers at the top (atria) collect blood from the body and the lungs.
The two at the bottom (ventricles) pump blood to the lungs and body.
Why are ventricles bigger and more muscular than atria?
Because blood is pumped out of the heart at greater pressure from the ventricles so they need to withstand this pressure
What is the basic difference between the left and right chambers of the heart?
Right= de oxygenated Left= oxygenated
Why does the heart have its own blood supply?
The heart is a muscle and needs a constant supply of oxygen and nutrients and therefore requires its own blood supply in order to keep beating
What role do valves play in the heart?
To ensure blood only moves one way
In sequence, outline the path of blood through the heart and lungs
Lungs -> L.A -> L.V -> Muscle -> R.A -> R.V -> lungs
What is systole?
The phase of the heartbeat when he heart contracts and pumps blood from the chambers into the arteries
What is diastole
The phase of the heartbeat where the heart relaxes and allows the chambers to fill with blood
What is stroke volume?
The amount of blood ejected by the left ventricle in one contraction
What effect does exercise have on stroke volume?
Increase stroke volume as more oxygen is needed to help the muscles contract/relax
What is cardiac output?
The amount of blood pumped by the heart per minute
Wha Tis the formula for cardiac output?
CO=SVxHR
cardiac output = stroke volume X heart rate
What affect does exercise have on cardiac output?
Exercise causes cardiac output to increase due to and increase in stroke volume and heart rate
What is heart rate?
The number of times a persons heart beats per minute
