adaptations in body physiology L19-20

Question 1

VO2max

Answer 1

maximal amount of oxygen delivered to working tissues and utilised in aerobic metabolism
max rate of aerobic metabolism

Question 2

VO2

Answer 2

measure of aerobic metabolism rate

Question 3

physiological factors of VO2

Answer 3

utilization theory (O2 utilization of body)
presentation theory (delivery of O2)

Question 4

graded exercise test

Answer 4

8-10 mins of exercise w large muscle groups
^load stepwise every 4-6 mins
e.g. ramp protocols/ square wave test

Question 5

ventilatory response to exercise

Answer 5

immediate increase w feed forward reflex
peripheral/ central chemoreceptors control rate
VR stays elevated until ATP stores return to normal

Question 6

feed forward reflex

Answer 6

muscle/ joint proprioceptors> motor cortex> resp centre> ^ventilation

Question 7

VENTILATORY THRESHOLD

Answer 7

point at which ventilation starts to increase at faster rate than VO2

Question 8

fick equation

Answer 8

VO2max = Q*(a-v)O2c

Question 9

heart rate ^ mediation

Answer 9

^SA node sympathetic activation
decreasing para

Question 10

stroke volume control

Answer 10

^ symp output ^contractility
^end diastolic volume
results from cardiac dimension/ blood volume/ venous return changes

Question 11

Frank-starling mechanism

Answer 11

^ventricular filling and emptying

Question 12

oxygen extraction

Answer 12

more effective flow distribution
^extraction ability

Question 13

oxygen extraction factors affecting

Answer 13

^capillarisation
^capillary to fibre ratio
^aerobic capability

Question 14

^altitude effects

Answer 14

hypobaria
same %O2
decreasing O2pp

Question 15

dalton’s law

Answer 15

sum of partial pressures = total pressure

Question 16

hypobaric environment responses

Answer 16

^ventilation
chemoreceptors in carotid body react to decreasing O2pp

Question 17

acid-base homeostasis mechanisms

Answer 17

hypoxic ventilatory response
renal excretion of bicarbonate

Question 18

acid-base homeostasis preventions

Answer 18

^blood pH
blunted HVR
decreasing O2 saturation/ cerebral blood flow

Question 19

Chaynes stokes breathing

Answer 19

rapid breathing
pause deep breath rapid breaths

Question 20

renal HCO3 excretion

Answer 20

H2O + CO2 > H2CO3 > H+ + HCO3

Question 21

diamox

Answer 21

carbonic anhydrase inhibitor taken as prophylaxis

Question 22

renal compensation to decrease pH

Answer 22

decreased HCO3 absorption in proximal tubule
decreased H+ secretion by alpha-intercalated cells (acid retention)

Question 23

central / peripheral chemoreceptors action due to decreasing CO2/ ^pH

Answer 23

decreased CO2 central chemoreceptors decrease respiration
^H+ peripheral chemoreceptors increase respiration

Question 24

%saturation formula

Answer 24

O2Hb/ O2 capacity of Hb *100

Question 25

initial adaptations to ^altitude

Answer 25

^2,3-DPG
Hb releases O2 at higher pressure

Question 26

long-term adaptations to altitude

Answer 26

^RBC
^haematocrit
^capillary numbers

Question 27

initial haematocrit^ effects

Answer 27

^urination and water loss w ^respiration

Question 28

long-term haematocrit effects

Answer 28

^haemopoiesis
decrease in kidney oxygen tension
kidney releases erythropoietin

Question 29

angiogenesis

Answer 29

increase in number of capillaries due to altitude

Question 30

high altitude pulmonary oedema

Answer 30

alveolar hypoxia> hypoxic vasoconstriction> ^capillary pressure> oedema/ pulmonary wall damage/ ^hydrostatic pressure

Question 31

high altitude cerebral oedema

Answer 31

gradual 2-3 day onset/ fatal neurological condition

Question 32

vasogenic oedema

Answer 32

CNS fluid movement across blood-brain barrier ^intracranial pressure

Question 33

cytotoxic oedema

Answer 33

fluid cell retention in CNS ^intracranial pressure

Question 34

HACE/ HAPE treatment

Answer 34

nifedifine
dexamethasone