Circulatory Physiology Flashcards
○ Transports blood out of the heart
○ Receives the blood from the heart
○ Elastic
Arteries
Transports blood back from the heart
○ Have valves - formed by tunica intima
○ Some veins are valveless - Pulmonary vein
Veins
Counterpart of arterioles
■ Receives blood from capillaries
■ Carries deoxygenated blood
Venules
T or F
An increase of HR, increases cardiac output
TRUE
- the amount of blood pumped by the
heart per minute
Cardiac Output
the amount of blood pumped by the heart
for each contraction
Stroke Volume
blood returned to the heart, the amount
of cardiac output
Venous Return
Should blood vessels have a high capacitance?
No, because blood continuously flow into your blood vessels
○ Your venous system is 8 times more distensible, why your veins are the blood reservoir
Increase in tissue metabolism causes increase in
blood flow due to an increase demand for
oxygen and nutrients
Acute Control
Blood vessels valves produces dilator
substances
● A decrease in oxygen causes an increase of
vasodilator substances - histamine,
potassium ions, hydrogen ions
Vasodilator Theory
Absence of oxygen causes vasodilation
● No oxygen, no ATP, no energy, no
contraction
● A lack of glucose, you don’t have anything
to breakdown for energy
Oxygen Theory or Nutrient theory
Increase arterial pressure, increases oxygen
■ Vasodilator substances decreases due to the increase of oxygen since they are washed out by the increase in blood flow
Metabolic Theory
A sudden stretch of your small blood vessels cause by an increased blood pressure
■ This causes more stretch for your small blood vessels to contract - an intrinsic response of muscles
Myogenic Theory
- a vasodilator, increasing blood vessels, increasing blood flow
Nitric oxide