Lab (The heart)

Where does the left ventricle pump blood when it contracts?

Aorta

The condition known as atrial septal defect is characterized by the presence of a hole in the interatrial septum. How would this condition impact the normal pattern of blood flow? What effect would this have on the oxygenation of the blood?

Atrial septum defect would cause some of the blood to flow directly from the rightatrium to the left atrium, bypassing the pulmonary circuit. This would result in the presences of deoxygenated blood in the atrial systemic circuit, reducing the amount of oxygen available to the cells.

Where do arteries carry blood?

Away from the heart

High pressure in the systemic and pulmonary circuits often results in ventricular hypertrophy, in which the ventricle enlarges to pump against greater forces. Which side of the heart would be affected by high pressure in the pulmonary circuit? Which side of the heart would be affected by high pressure in the systemic circuits? Explain.

High pressure in pulmonary circuit- right side would be affected because the right side of the heart pushes blood through the pulmonary circuit so that it can be oxygenated in the lungs. High pressure in systemic circuit- left side affected because the left side of the heart pumps oxygenated blood to the entire body through this systemic system

Skeletal muscle cells exhibit a phenomenon known as recruitment, in which the number of muscle cells recruited to contract is proportional to the strength of muscle contraction needed. In this way, we activate a few fibers to produce a small contraction to pick up a piece of paper and we activate many fibers to produce a larger contraction to pick up a textbook. Would you expect to see recruitment in a cardiac muscle tissue? Why or why not?

No recruitment because cells are united by gap junctions so all cells contract in unison

When the pericardium fills with blood, it produces a condition called cardiac tamponade, which can be rapidly lethal. Why is this condition so dangerous?

Pericardium is not very distensible so it does not expand as it fills with blood. This puts pressure on the heart and prevents adequate filling

What is the exception for the artery that carries deoxygenated blood

The pulmonary artery carries deoxygenated blood that foes away from the heart to the lungs

What is the exception for the vein that carries oxygenated blood?

The pulmonary vein brings oxygenated blood back to the heart

One potential cause of valve dysfunction is rupture of the chordae tendineae. Why would this lead to valve dysfunction? Would this impact the atrioventricular valves, the semilunar valves, or both? Explain

This would only affect the AV valves because SL valves do not attach to chordae tendineae. If the chordae rupture, then the papillary muscles cannot keep the valve leaflets taut. This causes the valve leaflets to prolapse back into the atrium and blood to leak backwards when the ventricles contract.

In the heart dissection you performed, you saw the smooth texture of the valves and how the leaflets fit together. How do you think the function of the valves would be affected if the valves were tough and filled with calcium deposits? Explain.

Valves prevent backflow of blood in the heart. If they were less pliable they would not close properly and blood would flow backwards.

Is the blood carried to the heart generally oxygenated or deoxygenated?

deoxygenated

Where does the left atrium pump blood when it contracts?

left ventricle

Is the blood carried away from the heart oxygenated or deoxygenated?

oxygenated

Where does the right ventricle pump blood when it contracts?

pulmonary tunk

Where does the right atrium pump blood when it contracts?

right ventricle

Where do veins carry blood?

to the heart