Unit 1: Section 5 - Circulatory System Flashcards
The right side of the heart pumps what blood to were?
Deoxygenated to the lungs
The left side of the heart pumps what blood to were?
Oxygenated to the body
Where does deoxygenated blood enter the heart?
Vena cava
Where does deoxygenated blood leave the heart?
Pulmonary artery
Where dos oxygenated blood enter the heart?
Pulmonary vein
Where does oxygenated blood leave the heart?
Aorta
Are the atriums or ventricle at the bottom of the heart?
Ventricles
What valves control what blood enter the ventricles?
Atrioventricular valves
What valves control what blood leaves the ventricles?
Semi-lunar valves
On the drawing what side will the right atrium be on?
The left hand side
Where are cords attached in the heart and what is their purpose?
They attach the atrioventricular valve to the ventricles to stop them being forced up into the atria when the ventricles contract
Why does the left ventricle have a thicker more muscular wall?
Because it needs to contract powerfully to pump blood all the way around the body
Why do the ventricles have thicker walls than the atria?
Because they need to pump blood out of the heart where as the atria just need to pump it a small distance
Why are there valves in the heart?
To stop blood from flowing backwards
What happens when there is higher pressure behind a valve and when there is higher pressure in front of the valve?
Forced open
Forced shut
What does the cardiac muscle is myogenic mean?
It can contract and relax without receiving signals from nerves
What is the pace maker of the heart called
Sino atrial node (SAN)
How does the SAN make the left and right atria contract at the same time?
It sends out regular electrical waves to both atrial walls, which causes them to both contract
Why are the electrical impulses passed from the SAN to the AVN?
There is non conducting tissue preventing the electrical waves reaching the ventricles, so to get these to contract the waves have to be passed to the AVN.
What does AVN stand for?
atrioventricular node