lec 9 circulation Flashcards
a humans internal transport system is the..?
circulatory system
the circulatory system is composed of…?
a muscular heart that circulates blood thru blood vessels
which blood vessel carries blood away from the heart, to the rest of the body?
thick-walled arteries
what do tiny capillaries do?
allow exchange of materials b/w blood and surrounding tissue
which blood vessel collects blood from the body to bring it back to the heart?
thick-walled veins
our circulatory system is a closed system, what does this mean?
blood never leaves the blood vessels
what are the 4 chambers of the human heart?
right atrium, right ventricle, left atrium, left ventricle
explain the role of each chamber within the heart
right atrium:
-receives blood from body
-pumps blood to right ventricle
right ventricle:
-pumps blood to lungs
left atrium:
-receives blood from lungs
-pumps blood to left ventricle
left ventricle:
-pumps blood thru body
t/f heart valves open both ways
false, valves open one way
the sound of heartbeat results from..?
closing of the valves
how is the sound of a heartbeat described? explain where each of the sounds comes from
lub-dub sound
lub: valve b/w atrium and ventricle shuts
dub: vavle b/w ventricle and arteries shuts
what does blood pressure represent?
pressure change in arteries that receive blood from left ventricle
how is blood pressure represented?
120/80
first #: pressure generated from contraction of left ventricle
second#: pressure when ventricle relaxes+refills
what is important about capillaries and why?
narrow blood vessel lined by single layer of endothelial cells
materials can diffuse easily in and out
what diffuses in and out of capillaries?
in: nutrients
out: waste from metabolic processes
