Circulation and Immunity. Cardiovascular System The system consisting of the heart, blood vessels...

Circulation and Immunity

Cardiovascular System

The system consisting of the heart, blood vessels and blood that circulates through the body.

Cardiovascular System The human circulatory system performs four

key functions. It transports and delivers oxygen and

nutrients (e.g. minerals, vitamins, and glucose) to the body’s cells in exchange for carbon dioxide and wastes.

It transports chemical messengers, such as hormones throughout the body.

It distributes heat It defends against disease

Cardiac Output

Cardiac Output is the volume of blood pumped by the heart in one minute, which is equal to the product of stroke volume and heart rate.

Average Values

The average human male pumps out 70mL of blood per beat (60 mL for females) with an average resting heart rate is around 72 beats per minute.

Example Question A typical human male has a stroke volume

of 70 mL per beat and a resting heart rate of 72 beats per minute.

A. Calculate the cardiac out put. Express your answer in litres per minute.

B. Calculate the volume of blood that would be pumped in one day based upon the cardiac output.

Example Question A typical human male has a stroke volume

of 70 mL per beat and a resting heart rate of 72 beats per minute.

A. Calculate the cardiac out put. Express your answer in litres per minute.

Solution. Stroke volume = 70 mL/beat 70 mL x 1/1000mL = 0.070 L/beat

Example Question A typical human male has a stroke volume of

70 mL per beat and a resting heart rate of 72 beats per minute.

Solution. Cardiac output (stroke volume)x(heart rate) =(0.070 L/beat)x 72 (beats/min) = 5.04 L/min In one day 5.04 L/min x 1440 min/day = 7257.6 L = 7.3 x 103 L/day

Heart Diagram

Heart Diagram

Blood Flow

Blood Flow

Blood Flow

Blood Flow

Heart Beat

Diastole - the phase of the heart’s cycle where a chamber of the heart, either an atrium or a ventricle, relaxes and fills with blood. Semilunar valves closed - “dub” sound produced

Systole - the phase of the heart’s cycle when the ventricles contract to eject blood from within the chamber. AV vales closed - “lub” sound produced.

Heart Beat

Factors Affecting Heart Rate

Emotions ie. Fear anxiety External temperature. Hotter = Higher HR Activity level. Age. Older you get the lower your max HR Fitness level. Medical conditions.

Target Hear Rate for Exercise Your maximum heart rate is approximately

220 - your age.

Target Heat Rates

Personal Health Goal % of Max Heart Rate

Maintain fitness level 50 - 60%

Increase fat burning of weight loss

60 - 70%

Increase cardiovascular endurance

70 - 80%