Circulation/blood pressure

Question 1

Blood pressure

Answer 1

The force of the blood on the walls of the arteries

Measured with a sphygmomanometer, obtaining a systolic and diastolic pressure

Systolic pressure is when the ventricles contract

Diastolic pressure is when the ventricle relax

Question 2

How Blood Pressure is measured

Answer 2

Is measured in mm of Hg
Blood Pressure = Systolic pressure
Diastolic pressure
Normal blood pressure = 120/ 80
Highest in the aorta.
Blood pressure & velocity both decline as blood enters the arterioles.
The drop in pressure results from the resistance (friction) to blood flow.
Low blood pressure reduces your capacity to transport blood.
High blood pressure weakens & ruptures arterial walls.

Question 3

Systole (120 mm of Hg)

Answer 3

Atria contract to further fill the ventricles.
Tricuspid & bicuspid valves forced closed due to an increase in ventricular pressure.
Ventricles contract to force blood from the heart.
Pulmonary & aortic semi-lunar valves are open.

Question 4

Diastole (80 mm of Hg)

Answer 4

Blood enters all four chambers.
Pulmonary veins 🡪 left atrium.
Inferior & superior vena cava 🡪 right atrium.
Left & right AV valves are open.
Pulmonary & aortic semi-lunar valves are closed.

Question 5

Blood Pressure Regulation

Answer 5

Medulla oblongata regulates blood pressure by sending signals to receptors in body

When pressure is high:
Decreasing sympathetic impulses causes arteriole dilation
Increasing parasympathetic impulses causes heart rate to lower and stroke volume to decrease
Opposite for low pressure

Question 6

Electrocardiograph

Answer 6

a device that detects the electrical activity of the heart through electrodes placed on the body’s surface.

Question 7

Electrocardiogram (ECG)

Answer 7

ECG is a record of electrical impulses generated by a beating heart