BLOOD VESSLES

Question 1

Elastic arteries (like the aorta)

Answer 1

structure: located closest to the heart, have large diameters, thick tunica media with tons of elastin.

function: to conduct blood away from the heart pressure reservoirs

Question 2

Muscular arteries

Answer 2

structure: further away from the heart, thick tunica media, with tons of smooth muscle layers (less elastin)

function: distribute blood to the organs, perform vasoconstriction

Question 3

arterioles

Answer 3

structure: small diameter, has a few smooth muscles layers

function: constrict and dilatate to control blood flow entering capillary beds

Question 4

capillaries (3 kind)

Answer 4

structure: continuous fenestrated sinusoidal

function: site of exchange

Question 5

capillaries: Continouse

Answer 5

structure: simple squamous epithelium with intercellular clefts

Question 6

capillaries: special type: fenestrated

Answer 6

structure: have fenestra (windows) for filtration

i.e. in kidneys

Question 7

capillaries: special type: sinusoidal

Answer 7

structure: have very wide intercellular clefts to allow large particles and entire cells through

i.e. liver and bone marrow

Question 8

blood pressure

Answer 8

the force or push that exerts with in blood vessel walls

Question 9

pressure gradient

*Push from arterial to venous

Answer 9

gradient= difference between one side to another
blood will flow from areas of high pressure to low pressure, arterial systems start high while venous system has low pressure

Question 10

blood pressure from arterial system to venous system

Answer 10

i. arterial pressure:
high pressure and pulsatile
systolic pressure is high (~120 mmHg)
diastolic pressure is low (~80 mmHg)

ii. capillary pressure: low pressure but not 0 mmHg, there is some pressure so not completely 0 there is some push.

iii. venous pressure: very low, all the way down to 0 mmHg at the vena cava. Vena cava cannot pump alone which is why we need valves and external pumps

Question 11

Mean arterial pressure (MAP)

Answer 11

this is the average BBP in the arterial system.

Question 12

calculating blood pressure

Answer 12

recorded as a fraction 120/80
ventricular contraction= systolic pressure ~120 mmHg
ventricular relaxation= diastolic pressure
~80 mmHg

Question 13

calculating total peripheral resistance

Answer 13

anything that gets in the way of the flow (systemic circuit)

TPR= MAP/CO
CO= HR X SV

Question 14

calculating pulse pressure

Answer 14

recorded as a fraction 120/80
ventricular contraction= systolic pressure ~120 mmHg
ventricular relaxation= diastolic pressure
~80 mmHg

Question 15

calculating MAP

Answer 15

we want 70-100

MAP= diastolic pressure + 1/3 pulse pressure

ex: if 120/80

MAP= 80 + 40 = 93

Question 16

perfusion

Answer 16

the blood flow to organs and tissues to deliver O2 and nutrients

Question 17

intrinsic and extrinsic factors which determine tissue perfusion

intrinsic: autoregulation

Answer 17

b. intrinsic: autoregulation
in-house (open and close control flow)

i. goal: to maintain constant perfusion into tissues and organs

ii. metabolic: vasodilation occurs when (acts as triggers)
1. hypercapnia (high CO2)
2. acidosis (low pH)
3. hypoxia
4. elevated lactate

iii. myogenic (muscle)
1. high systemic BP stimulates vasoconstriction
2. low systemic BP stimulates vasodilation

c. extrinsic: neural and hormonal (previously converted)- ques coming from outside blood vessels

Question 18

capillary exchange and the pressure relationships of bulk flow

Answer 18

a. starling’s law of capillary exchange: osmotic pressure and hydrostatic pressure drive the movement of fluids. net filtration pressure depends on these forces.

Question 19

capillary exchange and the pressure relationships of bulk flow

Answer 19

b. on the arteriole end of capillaries:
i. osmotic pressure will want to: push fluids into capillaries

ii. hydrostatic pressure within capillaries, however, is: higher than OP/ stronger
 
iii. therefore fluids are pushed out of capillaries (AKA filtration)

Question 20

capillary exchange and the pressure relationships of bulk flow

Answer 20

c. on the venule end of capillaries:
i. hydrostatic pressure will want to: send fluids out of vessels

ii. osmotic pressure within capillaries, however is: stronger than HP

iii. therefore, fluids are pushed into capillaries (AKA reabsorption)

Question 21

hypertension

Answer 21

anything higher than 140/90

Question 22

hypotension

Answer 22

anything lower than 90/60