Cardiovascular phgy Flashcards
Functions of cardiovascular system part 1
- bringing nutrients into body (ex. from intestine to liver)
2.bringing fuel to cells (ex. glucose from liver to brain, you have 4 min to help someone in cardiac arrest since brain + heart has no internal source of energy)
3.bringing O2 from cells to lungs (mainly aerobic) - removal of waste products (ex. CO2 from lungs, ammonia in liver–>urea–>kidneys
- circulation of hormones (adrenaline from adrenal glands to heart muscle)
functions of cardiovascular system part 2
- circulation of immune cells and antibodies
- regulation of pH (ex. lungs, kidneys)
- H2O balance (ex. excercise, dehydration, overhydration)
- thermoregulation (ex. excercise, hypothermia, hypothermia, muscle is not very efficient, about 85% energy is converted into heat )
myocyte, what do they generate, how many capillaries are there per myocyte
-what forms conc. gradient
cells of the heart, they generate the contractile force of the heart
-every myocyte has 4-5 capillaries around it (where O2 conc is high)
-need dense network of capillaries to form conc gradient
-heart has highest O2 consumption
Flow factors
- concentration gradient
- diffusion constant
- cross sectional area
Diffusion flow formula?
what is flux formula
how much faster does Co2 diffuse
Flow= diffusion constant(Cout-Cin/d)Area
flux=flow/area= diffusion constant*(Cout-Cin/d)
Co2 diffuses 20 times easier compared to O2 when in water
how O2 gets into RBC
what are the barriers
O2 moves through the barriers through process of diffusion to get to RBC
6 barriers:
interior alveolus–>alveolar membrane–>interstitial space–>wall of capillary–>blood plasma–>RBC membrane
How O2 gets into alveolus
convective or bulk flow-driven by a pressure difference caused by the negative pressure in the lungs which causes air to get sucked in
capillary
they are 1 micron thick, and diffusion occurs through them bc of the short distance and high conc gradient
what are the 3 cardiovascular system components?
pump:heart
pipes: vessels
fluid: blood
insect circulation
it is open circulation–>end is open and blood goes out of the tube and percolates through the organs
-they have a dorsal aorta with 5 chambers (varies in diff insects)
-fluid pumped is haemolymph, not blood
piscine circulation(fish)
-closed, single loop circulation with 2 chambers (ventricle pumps to drive blood through entire system)
-has gill (oxygenates)+systemic (deoxygenates) capillaries
amphbian/reptilian circulation
What type of blood is returned and where
What gases can it exchange via blood and skin
what kind of sternum does it have
-closed, double loop circulation with 3 chambers (only 1 ventricle)
-deoxygenated blood returned to right atrium, them expeled into ventricle
-can exchange O2 + CO2 via blood and skin (pulmocutaneous system)
-has interatrial septum
Avian and Mammalian circulations
right heart- pulmonary circulation
left heart-sytemic ciruculation
closed, double loop circulation with 4 chambers
-interventricular septum (cardiac muscle) separates left+right ventricle (no mixing of blood)
what is haemodynamics
what are the forces involved
circulation and movement of blood across the body and the forces involved
factors;
volume
flow
pressure
resistance
compliance
haemodynamics volume in the body, what is in 1 unit of blood and what is stroke volume
blood volume-5L (75mL/kg, proportional to weight)
1 unit of blood- 450 mL (around 10% of blood volume)
stroke volume- 70mL (range is based on weight)
where is the blood in terms of parts of the body and its percent in each area?
pulmonary circulation-12%
heart-9%
arteries- 11% (site for resistance to flow)
arterioles and capillaries- 7%
veins and venules- 61% (capacity for storage)
what is the cardiac and venous output equal to
cardiac output and venous return are equal (5,000ml/min)
flow
what is the cardiac output value
What happens when blood moves to the lumen
=volume/time
or =area*velocity (or mean velocity if its not the same at all points)
cardiac output=5L/min
-when the blood moves into lumen, an equal amount is ejected out from vessel
types of blood vessels that are oxygenated and deoxygenated
oxygenated-ALSAC
aorta (comes out of left ventricle)
-large artery
-small artery
-arteriole
-capillaries (they join into venule)
Dexygenated- VVVc
-venule (joins into vein)
-vein
-vena cava (2 of them)
inferior vena cava (goes into right atrium)
superior vena cava (drains upper part of body)
resistance vessels
only small arteries and arterioles are resistance vessels (not all arteries)
number and dimensions of vessels
aorta-only 1 (long +thick)
arteries+veins similar amount/size
capillaries- billions, very small and thin
venules-100 million, larger than capillary smaller in thickness than arteriole
vena cava- 2 (thick and long)
RBC has diameter of 7.2 micrometers but is a thin disc so can fold and get through smaller vessels like capillaries (6 micrometer)
arterial tree, how is it made?
cast- made from evacuating blood from arterial system and replacing blood with substance that will harden, the tissue around is digested
cross sectional area and flow velocity, what happens as you go down the arterial tree to the speed and the cross sxn area?
as you move down arterial tree, total cross sxn area increases (capillaries have high cross sxn area)
-speed of flow decreases as area increases to maintain sum of 5L/min
-sum of 2 vena cava are is larger than aorta so it has smaller flow
4 advantages of branching network
- any cell is very close to capillary (allows for exchange)
- high total area of the walls of capillaries (area of vessel decreses but there are high number of capillaries)
- low blood flow velocity in capillaries ( allows time for exchange)
- high total cross sxn area (increase in area=resistance is dropped)
