4 key functions of the circulatory system
1) transports and delivers O2 and nutrients to the cells in exchange for CO2 and waste materials nutrients: minerals, vitamins, glucose 2) transports and delivers chemical messengers throughout the body chemical messenger: hormones 3) regulates body temperature 4) defends against disease
3 major components of the circulatory or cardiovascular system
heart blood vessels blood
in which direction is blood pumped? - from veins to arteries or - from arteries to veins
from arteries to veins
does the veins keep the blood moving in one direction?
yes
what connects arteries to veins
capillaries
are heart, arteries and veins all connected?
yes
cardiac output definition
volume of blood pumped by the heart PER minute
the greater the value of cardiac output (4)
- the better the heart as a pump - the stronger the heart is as a muscle - the more fit the person is - the bigger the value of stroke volume
how to determine cardiac output
(stroke volume x heart rate)
stroke volume definition (2)
- volume of blood pumped by heart PER beat - The quantity of blood pumped from the hearts left ventricle during each contraction PER beat
average stroke volume of adult … - male - female
- male is 70 mL / beat - female is 60 mL / beat
the greater the value of stroke volume…(4)
- the lower the value of RHR - the better the heart as a pump - the stronger the heart is as a muscle - the more fit the person is
RHR definition (1)
of contraction of the heart that occur PER minute while the body is at a complete rest
Heart rate definition
- how many times the heart beats PER minute
Why does the heart rate vary?
The heart rate can vary according to the body’s physical needs, including the need to absorb oxygen and excrete carbon dioxide
What determines how effective the heart is as a pump
- stroke volume (big value)
- cardiac output (big value)
resting heart rate (small value
