the heart and blood vessels Flashcards
what is the septum
a muscle wall that separates left and right atriums and ventricles
where is the atria located and what does it do
located at the top of heart
receives blood and pumps it into ventricles
what type of blood does the right atrium receive
receives deoxygenated blood from the body
what type of blood does the left atrium receive
receives oxygenated blood from the lungs
whee is the ventricle located
bottom on the heart
what does the right ventricle do
pumps blood to pulmonary circuit (lungs)
what does the left ventricle do
pumps blood to the systemic circuit (rest of body)
why is the heart surrounded by
pericardium which is a fluid filled membrane that protects heart from friction
how much oxygen does the heart need that’s in blood
%10
the heart has its own supply of coronary blood vessels what do they do?
Coronary blood vessels
They provide heart muscle cells with oxygen and nutrients and remove waste
why are the walls of ventricles much thicker than than the atria?
Ventricles have to pump blood over greater distances
At rest and maximum output how much can the heart pump?
at rest 5 L per minute
At maximum output, 25 L a minute
What are the steps in circulation?
1) deoxygenated blood enters right atrium through inferior and superior vena cava
2) right atrium contracts, blood goes to right ventricle
3)right ventricle contracts blood goes through pulonmary arteries to lung and picks up oxygen and realeases CO2
4)oxygenated blood from lungs enter left atrium from pulmonary veins
5)left atrium contract blood goes to left ventricle
6)left ventricle contracts blood goes to aorta
7)Aorta branches into major arteries that send blood to body
8) bloody go from arteries to capillary networks to veins to inferior and superior vena cava
Where is the semilunar valves located and what do they do
located between left ventricle and aorta and right ventricle and pulmonary artery
prevents back flow of blood when ventricles relax
where are the AV valve located and what do they do
located between atria and ventricles
prevents blood from going back into atria when ventricles contract
What is the Chordae tendinee
tendons that support AV valves
what three types of blood vessels does the circulatory system have
arteries
veins
capillaries
which way do arteries and arterioles take blood to heart
what type of blood do they carry
-take blood away from heart
-carry’s mostly oxygenated blood except )pulmonary artery)
What does the artery wall consist of
smooth muscle that constrict to regulate blood flow and pressure
what does the venules do
drain blood from capillaries, then join to form veins that take blood to heart
do veins have more or less smooth muscle and connective tissues and arteries?
Less
What’s an example of a one way valve that veins contain?
Venus valves that prevent backward flow of blood when closed
what does contraction of skeletal muscle do?
Squeezes veins pushing blood towards heart
why are capillary walls only one cell thick?
To allow fast exchange of materials and its diameter is about the same size as one red blood cell
are all capillary beds open at the same time
No
what do precapillary sphincter muscles do?
Open and close capillaries
What causes semilunar valves to close?
backflow of blood in aorta and pulmonary artery during diastole.
what sounds make Lub and Dub in the heart
LUB: occurs when AV valves close at the beginning of ventricular contraction
DUB: occurs when semilunar valves close at the beginning of ventricular relation
During systemic circulation what type of blood is carried away from the heart.
During pulmonary circulation what type of blood is carried away from the heart.
oxygenated
deoxygenated
- You are told that your blood pressure is 108/72. What
does the 72 refer to?
diastolic pressure
