00:01
This question here says, during the cardiac cycle at the time of the highest ventricular pressure, what is the status of the heart valves? so in this case, if you have the left ventricle, i suppose, you have here the left, this is the left ventricle, this is the aorta, and this is the left atrium.
00:19
So it says, at the time of the highest ventricular pressure, it means when the pressure here is very high.
00:25
What is going to happen when you have a very high pressure in the left ventricle? well, practically, it is going to overcome the pressure in the aorta, and as fluid moves from higher pressure to lower pressures, then fluid is going to move to the aorta from the left ventricle.
00:41
So in this case, this valve should be open.
00:44
It means the aortic valve is going to be open, and this valve is going to remain closed because in order to prevent blood regurgitation back to the left atrium.
00:53
So in this case, you have that, atrioventricular valves are closed, and the semilunar valves are open.
00:59
So you have that option b is the answer for this question.
01:02
Then it says, what causes air to move into the lungs during inspiration? so in this case, the answer is going to be option d, because remember that in this case, in order for air to move into the lungs, the pressure in the air or the pressure gradient between the atmosphere, it means in the air, atmosphere must be higher than the pressure in the alveoli...