Cardiac Output and Blood Pressure

What does adrenaline do?

Adrenaline enhances the response of the sympathetic nervous system.

How does adrenaline increase blood pressure?

Adrenaline increases blood pressure by 1. Increasing the heart rate and the force of contraction. 2. constricting many arterioles. 3. increasing venous pressure.

Why are arterioles the major influence on peripheral resistance?

Arterioles are the major influence on peripheral resistance because they change diameter in response to the nervous system and chemicals.

What factors influence an individuals blood pressure?

BP is influenced by genetic and lifestyle factors e.g. body weight, exercise, diet

What do baroreceptors do and where are they found?

Baroreceptors detect changes in blood pressure. They are found in the carotid arteries and aortic arch.

What happens when baroreceptors think BP is too high?

Baroreceptors send impulses to the cardiac and vasomotor centres so they reduce sympathetic NS stimulation.

What controls the diameter of blood vessels?

Diameter of blood vessels is controlled by the vasomotor centre in the medulla oblongata.

What is diastolic blood pressure?

Diastolic blood pressure is the force exerted against the wall of the artery during left ventricular diastole.

What are the roles of the kidneys in regards to blood pressure?

Kidneys affect blood pressure by regulating blood volume. Kidneys increase urine output when blood volume is high.

What hormone to the kidneys produce?

Kidneys produce the hormone renin which leads to vasoconstriction.

What does mean arterial pressure show?

Mean arterial pressure calculates the average blood pressure.

What is mean arterial pressure?

Mean arterial pressure is the difference between the systolic and diastolic pressure.

What is systolic blood pressure?

Systolic blood pressure is the force exerted against the wall of the artery during the left ventricular systole.

What factors affect the stroke volume?

The factors that affect stroke volume are 1. The amount of blood in the ventricle before it contracts. 2. How strongly the ventricle can contract. 3. The resistance in the aorta or pulmonary trunk.

What are the three functions of blood pressure?

The functions of blood pressure are to 1. push blood around the body. 2. Capillary exchange between blood and cells. 3. Filtration of blood in the kidneys.

What is the cardiac output?

Cardiac output is the amount of blood pumped out by one ventricle in one minute. (Stroke volume x Heart rate)

What are three age related changes to the cardiovascular system?

1. Loss of cardiac muscle size and strength. 2. Decreased compliance of the aorta. 3. Increase in systolic blood pressure.

What four things affect blood pressure?

Blood pressure is affected by 1. peripheral resistance. 2. blood vessel diameter 3. blood viscosity. 4. Blood vessel length.

What is blood pressure?

Blood pressure is the force that blood exerts on the wall of the artery.