control of ventilation and adaptation to training

Question 1

principle 1

Answer 1

reason for the abrupt rise at the onset of exercise

Question 2

principle 1

Answer 2

-immediate increase in ventilation begins before muscle contractions
- anticipatory response from central command (cerebral cortex)

Question 3

f =

Answer 3

frequency breathing pattern

Question 4

Principle 2

Answer 4

-TV crees more than the frequency of breathing in moderate exercise
- as exercise intensity increases above lactate threshold, frequency increases

Question 5

principle 3

Answer 5

gradual rise to steady state

Question 6

principle 3

Answer 6

• gradual 2nd phase of ventilation
• chemoreceptors
  -mechanorecetpros
• other receptors

Question 7

principle 4

Answer 7

gradual decrease - recovery from exercise

Question 8

delayed ventilation reverie after exercise may be regulated by

Answer 8

blood pH, PCO2 and temperature

Question 9

principle 5

Answer 9

relationship between VE and VO2

Question 10

VO2 is

Answer 10

how much oxygen consumption

Question 11

principle 5

Answer 11

ventilation increase in proportional to metabolic demand of muscle up to a point (nonlinear increase)

Question 12

why is there a steeper rise around 70% of VO2max

Answer 12

sharper increase could indicate reach of lactate threshold - producing more hydrogen ions and CO2

Question 13

the repository system pacemaker

Answer 13

PreBotzinger complex (PreBoC)

Question 14

inspiration is

Answer 14

active

Question 15

expiration is

Answer 15

passive

Question 16

the pacemaker is which part of the group

Answer 16

inspiratory group of neurons that activate the respiratory muscles

Question 17

inspiratory muscles

Answer 17

diaphragm
- external intercostals

Question 18

expiratory muscles

Answer 18

• rectus abdominis
• internal intercostals

Question 19

a closet of neurons in the ventral respiratory group in the ventrolateral medulla that seems to be key in the generation of the respiratory rhythm

Answer 19

pre-botzinger complex

Question 20

the role of pre-botC with the dorsal respiratory group?

Answer 20

sends input via the phrenic nerve to the diaphragm and vita the intercostal nerves to the intercostal muscles

Question 21

an area in the medulla that receives sensory input forms the peripheral chemoreceptors and mechanoreceptors through the vagus nerve and glossopharyngeal nerves

Answer 21

nucleus tractus solitarius

Question 22

which neuron in the prefixal respiratory group appears to be involved in active expiration

Answer 22

retro trapezoid neurons

Question 23

pontine respiratory group purpose

Answer 23

talks with both the inspiratory and expiratory centers and higher brain centers to coordinate breathing under more active conditions

Question 24

high cardiac output during high intensity exercise result in the rapid movement of RBCs through the lung, which limits?

Answer 24

gas equilibrium to be achieved between the lung and blood

Question 25

central chemoreceptors (medulla)

Answer 25

- respond to changes in brain CSF - sensitive to PCO2 via H+

Question 26

an increase in either PCO2 or H+ results in?

Answer 26

central chemoreceptors sending afferent input into the respiratory center to increase ventilation

Question 27

perisperhal chemoreceptors

Answer 27

respond to changes in arterial blod - sensitive to PO2, H+, PCO2

Question 28

carotid bodies are sensitive to

Answer 28

increase in blood potassium levels, NE,, decrease in arterial PO2 and increased body temp

Question 29

location of peripheral chemoreceptors

Answer 29

location in the aortic arch and at the bifurcation of the common carotid artery

Question 30

under normal conditions (sea level) what drives ventilation

Answer 30

CO2

Question 31

exposure to an environment with a barometric pressure much lower than at sea level (high altitude) can cause?

Answer 31

a decreases in arterial PO2 and stimulate carotid bodies which in return signal the respiratory control center to increase ventilation

Question 32

hypoxic indicates low

Answer 32

PO2

Question 33

hypoxic threshold occurs at arterial

Answer 33

PO2 of 60 to 75mmHG

Question 34

the point on the PO?V2 curve where ventilation begins to rise rapidly is called the

Answer 34

hypoxic threshold

Question 35

the chemoreceptors are responsible for the increase in ventilation following expresoure to

Answer 35

low pO2 are the carotid bodies because the aortic and central chemoreceptors in humans do not respond to changes in PO2

Question 36

the initial increase in ventilation during exercise is the

Answer 36

central input

Question 37

peripheral input feeds into the

Answer 37

respiratory control center to fine tune its response

Question 38

chemoreceptors -->

Answer 38

central and peripheral

Question 39

central goes to

Answer 39

nucleus tractus solitarius --> PCO2, H+

Question 40

peripheral goes to

Answer 40

aortic arch and common carotid artery

Question 41

recepistaroy control center can be stimulated by (4)

Answer 41

- higher brain centers - peripheral chemoreceptors - respiratory muscles - skeletal muscles

Question 42

submaximal exercise primary drive

Answer 42

higher brain centers (central command)

Question 43

sub maximal exercise fine tubed by

Answer 43

humoral chemoreceptors and neural feedback from muscle

Question 44

heavy exercise

Answer 44

- nonlinear rise in VE occurs due to: increasing blood H+ stimulates carotid bodies - increase in K++, body temperature, and blood catecholamines may also stimulate breathing

Question 45

ventilation is lower during exercise following training

Answer 45

exercise ventilation's 20 to 30% lower at same sub maximal work rate

Question 46

mechanism for reductio in VE during exercise

Answer 46

train does not alter lung structure - normal lung exceeds demand for gas exchange - increase respiratory muscle strengh - changes in aerobic capacity of locomotor muscles

Question 47

changes in aerobic capacity of locomotor muscles depends on

Answer 47

- results in less production of H+ - less afferent feedback form muscle to stimulate breathing

Question 48

does pulmonary system limit exercise performance? Low to moderate intensity exercise

Answer 48

pulmonary system does not limit exercise tolerance

Question 49

does pulmonary system limit exercise performance? high intensity exercise

Answer 49

pulmonary ventilation/gas exchange is not a limitation in healthy individuals at sea level at most exercise intensities

Question 50

gas exchange does limit exercise performance in some elite endurance athletes

Answer 50

40 to 50% experience hypoxemia - V/Q mismatch - RB capillary transit time too short