Question

In humans, what does the normal systolic and diastolic blood pressure mean?

Answer 1

Systolic pressure and diastolic pressure:

1. Blood pressure is the force exerted by the blood on the arteries.
2. Blood pressure is measured with two numbers.
3. The first number is called systolic blood pressure, which is the pressure when the heart is contracting and pulling out blood.
4. The second number is called diastolic pressure, which is the blood pressure when the heart is relaxing and filling with blood.

Systolic pressure:

1. In humans, normal systolic pressure is about 120 mm Hg and diastolic pressure is 80 mm Hg.
2. Mitral and tricuspid valves open during ventricular diastole causing it to fill with blood.
3. Atria begin to contract, which is the atrial systole.
4. It forces blood into the ventricle.
5. The ventricle starts to contract and causes tricuspid valves to close.
6. This stops blood from flowing in or out.

Diastolic pressure:

1. Contractions during the systole result in the rise of pressure in ventricles quickly.
2. It causes the aortic and pulmonary valves close valves to open and blood ejected out of the ventricles.
3. When ventricle pressure falls, aortic and pulmonary valves close.
4. As pressure falls, atria begin refilling blood as blood flows to the right atrium and into the left atrium.
5. As the ventricle relaxes, the mitral and tricuspid valves open.
6. The ventricular diastole occurs again.
7. Therefore, systolic pressure is the pressure when the heart contracts, and diastolic pressure is the pressure when the heart relaxes.