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
T or F
When your blood is thick, their is an increase of shear stress because it can tear, releasing endothelin damaging the
endothelium - the Intimal Injury
TRUE
is a powerful vasoconstrictor, it is released in response to an intimal injury
Endothelin
There is a formation of new channels
● Allows at least partial release of blood in tissues
Collateral Circulation
Pressure within your arteries every heartbeat
Systolic Blood Pressure
Pressure within your artery when your heart is at rest
Diastolic Blood Pressure
Difference of the systolic and diastolic blood pressure
○ Normal is at 120/80
Pulse Pressure
Greater the stroke volume, ___amount of blood
that must be accommodated in every heartbeat
Greater the stroke volume, greater amount of blood
that must be accommodated in every heartbeat
The __the compliance, the greater the rise of
pressure pumped into the arteries
○ Lesser factor we consider is the character of ejection
of the heart during systole
The lesser the compliance, the greater the rise of
pressure pumped into the arteries
○ Lesser factor we consider is the character of ejection
of the heart during systole
Type of heart valve disease or valvular heart disease
○ The valve narrows and doesn’t open fully, wherein blood decreases and blocks to blood flow in the heart to the aorta and to the rest of the body
Aortic Valve Stenosis
A persistent opening between the two major blood
vessels
○ A normal part of the baby’s circulatory system
○ If it remains open after birth, it’s Patent Ductus
Arteriosus
○ The blood flows backward, the diastolic pressure falls
very low before the next heartbeat
Ductus Arteriosus
Occurs when your heart aortic valve doesn’t close
tightly, results to a backflow of blood to the left
ventricle
○ Aortic valve is absent, therefore, the blood flows
immediately back and the aortic pressure falls all the
way to 0
Aortic Regurgitation
What will happen if If RAP increase above its normal value 0mmHg,
the blood begins to back up in the large veins
T or F
If RA pressure is greater as high as 4 to 6 mmHg, their
will be a rise in peripheral venous pressure in the limbs
and elsewhere
TRUE
More than __% of blood is in the veins , there will be a
greater compliance of the venous system
60%
Source of blood
○ Spleen -
○ Liver -
○ Large Abdominal Veins -
○ Venous plexus beneath the skin
○ Heart and lungs -
Source of blood
○ Spleen - can decrease in size
○ Liver - they have sinuses
○ Large Abdominal Veins - contributes as much as 300 microliters of blood
○ Venous plexus beneath the skin
○ Heart and lungs - main contributor
