The Heart Flashcards
(32 cards)
What side of the heart pumps deoxygenated blood and where is the blood pumped to
The right side of the heart pumps deoxygenated blood and the blood is pumped to the lungs
What side of the heart pumps oxygenated blood and where does the blood get pumped to
The left side and the blood is pumped to the rest of the body
What is the function of valves in the heart
To prevent blood from flowing the wrong way
Which valves link the atria to the ventricles
Atrioventricular valves
What valves link the ventricles to the pulmonary artery and aorta
Semi lunar valves
Valves can open both way. True or false?
False. Valves can open one way.
What determines if the valves are open or closed
Whether they are open or closed depends on the relative pressure of the heart chambers
If there’s a higher pressure behind the valve is the valve forced open or shut?
It’s forced open
If there’s a higher pressure in front of the valve is it forced open or shut?
It’s forced shut
What equipment would be needed to carry out a heart dissection
Equipment: Pig or cow’s heart, a dissecting tray, a scalpel, an apron and lab gloves
How would you externally examine the heart during the heart dissection?
-Look at the outside of the heart and try to identify the four main vessels attached to it
- Feel inside the vessels to help you, remember that arteries are thick and rubbery but veins are much thinner
- Identify the left and right atria, the left and right ventricles and the coronary arteries. Draw a sketch of the outside of the heart that has labels.
How would you internally examine the heart?
-Cut across the lines shown on the diagram to look inside each ventricle. Record and measure the thickness of the ventricles walls and note difference between the two if there are
-Cut open the atria and look inside them too, see if the walls are thicker or thinner than ventricle walls
-Find the atrioventricular valves, followed by semi lunar valves, look at the structure of the valves
- Draw a sketch to show the valves and the inside of the atria and ventricles
What is the cardiac cycle
The cardiac cycle is an ongoing sequence of contraction and relaxation of the atria and ventricles that keeps blood continuously circulating round the body.
What happens because of the volume of the atria and ventricles changing as they contract and relax
The volumes of the atria and ventricles changes as they contract and relax. Altering the pressure in each chamber. This cause valves to open and close, which directs the blood flow through the heart.
What is the first stage of the cardiac cycle
Ventricles relax, atria contract
During stage 1 of the cardiac cycle what happens to the atria and ventricles.
The ventricles relax and the atria contracts
Why does the atria contract in stage 1 of the cardiac cycle
The atria contracts, which decreases their volume and increases their pressure. This pushes blood into the ventricles through the atrioventricular valve.
Through which valves does the blood pass through on stage 1 ?
Atrioventricular valves
Is there an increase or decrease in the ventricular volume and pressure as the ventricles receive the ejected blood of the contracting atria?
There’s a slight increase in ventricular pressure and volume.
What happens to the ventricles and atria in stage 2 of the cardiac cycle.
Ventricles contract, atria relax
What happens to the ventricles as they contract in stage 2 of the cardiac cycle?
The ventricles contract decreasing their volume and increasing their pressure.
In stage 2, when the pressure becomes higher in the ventricles than the atria, what happens to the atrioventricular valves?
Forces the atrioventricular valves shut to prevent back flow
Where does the blood move to in stage 2?
Blood is forced out into the pulmonary artery and aorta
What happens to the ventricles and atria in stage 3
The ventricles relax and atria relax
