The heart

Question 1

name and describe the two valves in the heart

Answer 1

• semi-lunar valves= in aorta and pulmonary artery
• Atrioventricular valves=between atria and ventricles. The left side is called the Bicuspid valve, the right side is called the Tricuspid valve.

Question 2

name and describe the two veins in the heart

Answer 2

• vena cava (means body vein) carries deoxygenated blood from the body into the right atrium
• pulmonary vein= carries oxygenated blood from the lungs to the left atrium

Question 3

name and describe the two arteries in the heart

Answer 3

• Pulmonary artery= carries deoxygenated blood from the right ventricle to the lungs to become oxygenated
• Aorta= carries oxygenated blood from the left ventricle to the rest of the body

Question 4

what is unique about cardiac muscle?

Answer 4

• it is myogenic, meaning it can contract and relax without nervous or hormonal stimulation.
• it never fatigues as long as it has a supply of oxygen

Question 5

how does a heart attack happen?

Answer 5

• coronary arteries supply the cardiac muscle with oxygenated blood
• these branch off from the aorta
• if they become blocked cardiac muscle wont receive oxygen, therefore will not be able to respire and the cells will die.
• this causes a heart attack

Question 6

what do tendinous cords do?

Answer 6

stop valves from turning inside out

Question 7

what is the differences between the tricuspid and bicuspid valve?

Answer 7

tricuspid has 3 flaps and is on the left side of the heart
bicuspid has 2 flaps and is located on the right side of the heart

Question 8

describe diastole

Answer 8

the heart relaxes. The atria and then the ventricles fill with blood. The volume and pressure of the blood in the heart build as the heart fills, but the pressure in the arteries is a minimum.

Question 9

describe systole

Answer 9

the heart contracts. The atria contract (atrial systole), closely followed by the ventricles (ventricular systole). The pressure inside the heart increases dramatically and blood is forced out of the right side of the heart to the lungs and from the left side to the main body circulation. The volume and pressure of the blood in the heart are low at the end of systole, and the blood pressure in the arteries is at its maximum

Question 10

what are the two sound of the heartbeat described as?

Answer 10

lub- dub

Question 11

what makes the sound lub in the heart?

Answer 11

The first sound comes as blood is forced against the atrio-ventricular valves as the ventricles contract.

Question 12

what makes the sound dub in the heart?