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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
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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
Maintain fitness level
% of Max Heart
Rate
50 - 60%
Increase fat burning of 60 - 70%
weight loss
Increase cardiovascular 70 - 80%
endurance