5. The Heart Flashcards
The heart is two separate pumps lying side by side - which side deals with oxygenated blood and which side deals with deoxygenated blood?
The left deals with oxygenated blood and the right with deoxygenated
What is the heart?
The heart is a muscular organ that lies in the thoracic cavity behind the sternum.
Each pump of the heart has two chambers:
The atrium
The ventricle
Describe the atrium
thin-walled and elastic and streches as it collects blood. It only has to pump blood a short distance to the ventricle and therefore only has a thin muscular wall.
Describe the ventricle
It has a much thicker muscular wall as it must pump blood some distance, either to the lungs or to the rest of the body.
Why do we have a double circulatory system e.g two pumps
Because of the large drop in pressure in the capillaries in the lungs which would cause the blood to be distributed very slowly to the rest of the body.
How far does the right ventricle have to pump blood and what consequence does this have?
It pumps blood to the lungs-a distance of only a few centimetres and therefore it have a thinner muscular wall than the left ventricle.
How thick is the wall of the left ventricle?
It has a thick muscular wall as it must pump blood to the extremities of the body - a distance of 1.5m
Each of the sides of the heart contract…
At the same time as each other.
Name the valves on the left side of the heart.
The left avioventricular (bicuspid) valves - they form two cup shaped flaps on the left side of the heart
Name the valves on the right side of the heart.
The right avioventricular (tricuspid) valves - three cup-shaped flaps on the right side of the heart.
Where do the ventricles pump blood?
Away from the heart and into the arteries
Which vessel does the atria receive blood from?
The veins
Vessels connecting the heart to the lungs are called…
Pulmonary vessels
Where is the aorta connected and which type of blood does it carry?
The aorta is connected to the left ventricle and carries oxygenated blood to all parts of the body except the lungs.
Where is the vena cava connected and which type of blood does it carry?
The vena cava carries deoxygenated blood to the heart from the body and it is connected to the right atrium.