Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Exercise Physiology > Chapter 10 > Flashcards

Chapter 10 Flashcards

1
Q

pulmonary respiration

A

ventilation (breathing)
refers to the exchange of O2 and CO2 in the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

cellular respiration

A

refers to the O2 utilization and CO2 production by the tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

purposes of the respiratory system during exercise

A

gas exchange between environment and the body
regulation of acid-base balance during exercise (regulating blood pH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

ventilation

A

movement of air due to pressure differences
occurs via bulk flow (from high to low pressure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

inspiration

A

when the pressure in the lungs < atmospheric pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

expiration

A

when the pressure in the lungs > atmospheric pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what happens to the diaphragm and volume of the lungs during inspiration

A

diaphragm pushes down, ribs lift outward
volume of lungs is increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what happens to diaphragm and volume of lungs during expiration

A

diaphragm relaxes, ribs pulled inward
volume of lungs decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

pulmonary ventilation

A

aka minute ventilation (Ve)
the amount of air moved in or out of the lungs per minute (L/min)
composed of tidal volume and breathing frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

tidal volume

A

VT
amount of air moved per breath (L/breath)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

breathing frequency

A

f
number of breaths per minute (breaths/minute)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how to calculate Ve

A

Ve=VT x f

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what happens to Ve as you increase exercise intensity

A

increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what happens to tidal volume and breathing frequency during graded exercise

A

increase as intensity increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what produces inspiration and expiration at rest

A

produced by the contraction and relaxation of the diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what controls ventilation at rest

A

somatic motor neurons in the spinal cord and the respiratory control center in the medulla oblongata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the 2 main forms of input to the respiratory control center

A

1) neural input
2) humoral chemoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

neural input stems from

A

motor cortex and skeletal muscle mechanoreceptors

if you stimulate the muscle spindles, golgi tendon organs, and joint pressure receptors, they will all send input to respiratory control center which tells the lungs to increase ventilation due to increased movement in skeletal muscles
if you increase movement in skeletal muscles, you need to deliver more O2 to those tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

humoral chemoreceptors: 2 kinds

A

found in the blood and are made up of central and peripheral chemoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

central chemoreceptors

A

CNS
located in medulla
detect the presence of PCO2 and H+ concentration in the CSF by sensing for changes in partial pressure of CO2 and H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

peripheral chemoreceptors

A

located in aortic and carotid bodies
detect both what is in CNS (partial pressure of CO2 and H+) but also picks up changes in PO2 and K+

senses changes in PO2, PCO2, [H+], and K+ in blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

primary increase in ventilation during submax exercise is due to

A

neural input

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

increase in ventilation during maximal exercise is driven by

A

humoral chemoreceptors (both central and peripheral)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

pulmonary artery receives

A

mixed venous blood from right ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

oxygenated blood is returned to

A

left atrium via pulmonary vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

after oxygenated blood is returned to LA via pulmonary vein

A

O2 is not in LV and sends blood out to the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

how is pulmonary circulation possible

A

its a low pressure (closed) system with a rate of blood flow = to the systemic circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

during resting (conditions) such as standing, where is most of blood flow directed to in the pulmonary system

A

to the bottom (base) of the lungs due to gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

during upright exercise, what happens to blood flow in the lungs

A

bloodflow increases at the top of the lungs (apex)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

pulmonary arteriole contains

A

mixed venous blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

pulmonary venule contains

A

oxygenated blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

key characteristic of pulmonary capillaries

A

highly vascularized meaning there are lots of blood/blood vessels that have more capillaries as opposed to large vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

why is it beneficial to have a capillary network around the arterioles

A

if trying to diffuse O2 into the blood, need to have it as a capillary network to slow down blood flow to allow O2 to diffuse across membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

ventilation-perfusion ratios

A

how quickly are we moving air into alveoli and how quickly is blood moving past the alveoli (how well matched is bloodflow to ventilation)
(V/Q)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is the ideal V/Q

A

~1.0 (or above if exercising/bloodflow is high)

36
Q

how to calculate VQ ratio

A

V(A)/Q

V(A)= volume of air moved into alveoli
Q= bloodflow going past alveoli

Va= rate of ventilation (pulmonary ventilation)
Q= rate of perfusion (cardiac output)

37
Q

at the base of the lungs what does the V/Q ratio look like and why

A

less than 1 because ventilation < blood flow at the base of the lung

(overperfused relative to ventilation meaning that blood flow/cardiac output much greater than ventilation or Q>Va)

38
Q

at the apex of the lungs what does V/Q ratio look like and why

A

VQ>1 because ventilation > blood flow

(underperfused relative to ventilation meaning that blood flow, or cardiac output, is much less than ventilation or Va>Q)

39
Q

exercise induced asthma (bronchoconstriction) is caused by

A

contraction of smooth muscle around the airways (bronchospasms) and mucus in the airways during or after exercise
marked by wheezing sound and labored breathing (dyspnea)

occurs in >10% of elite endurance athletes

if managed correctly, does not impair performance (usually people take vasodilator)

40
Q

what happens to VQ ratio in asthma

A

perfusion increased
Va is decreased
V/Q ratio therefore <1

however this can be fixed by the pulmonary arteries themselves to constrict alveoli to help match the decrease in ventilation
by slowing down bloodflow into arteries, can pick up more O2

41
Q

what happens to V/Q ratio as a result of blood clot

A

increased ventilation
decreased perfusion
yields a V/Q >1

which can be corrected by pulmonary arteries dilating the arterioles to enhance Va and Q

blot clot travels through bloodstream and lodges itself in pulmonary arteries which prevents blood from being carried from heart to lungs. this impairs the lungs ability to oxygenate blood and decreases O2 in bloodstream. body activates respiratory control centers which leads to an increase in ventilation (hyperventilation) to bring in more O2 and expel high levels of CO2

42
Q

pulmonary capillary transit time

A

amount of time it takes RBCs to move past alveoli

43
Q

what kind of exercise improves V/Q

A

low to moderate intensity as you increase ventilation and bloodflow

44
Q

what exercise results in slight V/Q inequality

A

high intensity

because blood is moving too fast to fully be able to load RBCs with O2 as it passes alveoli, leading to lower partial pressure in arteries

45
Q

in general is it better for blood to move slower or faster past the arterioles

A

better to move the blood slower so that you can fully saturate RBCs

46
Q

99% of O2 transported is bound to

A

Hb

47
Q

oxyhemoglobin

A

Hb bound to O2

48
Q

deoxyhemoglobin

A

Hb not bound to O2

49
Q

the amount of O2 that can be transported per unit volume of blood is dependent on

A

the Hb concentration
arterial O2 saturation (can’t just have Hb in blood, have to have it as high oxyhemoglobin)
amount dissolved in plasma (minor contribution)- need to be able to diffuse O2 into liquids, so a high enough PO2 will diffuse O2 into plasma

50
Q

oxyhemoglobin dissociation curve

A

how we are moving O2 to different parts of the body

51
Q

oxyhemoglobin dissociation curve equation

A

deoxyhemoglobin + O2 <—-> Oxyhemoglobin

52
Q

direction of oxyhemoglobin reaction depends on

A

1) PO2 of the blood (higher PO2 shifts right)
2) Affinity between Hb and O2

53
Q

high PO2 results in and where

A

high PO2 at the lung will promote the formation of oxyhemoglobin, shifting the formula to the right

aka loading

54
Q

low PO2 results in and where

A

Low PO2 means there is a decrease in the affinity between Hb and O2, and O2 is being released to the tissues (unloading), driving the formula to the left

55
Q

increased PO2 drives sigmoidal curve

A

to the right

56
Q

decreased PO2 drives sigmoidal curve

A

to the left

57
Q

steep portion of sigmoidal curve represents

A

unloading

58
Q

flat portion of sigmoidal curve represents

A

loading

59
Q

effect of pH on O2-Hb Dissociation curve

A

decreased pH lowers Hb-O2 affinity which results in a rightward shift of the curve (Bohr effect) and facvors offloading of O2 to the tissues

increase H+ ions which will bind to Hb, Hb goes under conformational change and has less affinity to bind O2, easier to drop off O2

60
Q

during exercise, what happens to pH

A

pH decreases as there is an increase in blood H+
H+ ions bind to Hb, which reduces its O2 transport capacity

61
Q

effects of temperature on O2-Hb Dissociation curve

A

increased blood temperature lowers Hb-O2 affinity which results in a rightward shift of curve (makes it easier to deliver/offload O2)

62
Q

during exercise, how does an increase in body temperature affect the O2-Hb curve

A

an increase in temperature weakens the bond between O2 and Hb, which assists unloading of O2 to working muscle, shifts curve to the right

63
Q

effects of 2-3 DPG (or BPG) on O2-Hb curve

A

BPG is a byproduct of RBC glycolysis (since RBCs do not have nucleus or mitochondria, they rely on glycolysis to produce energy)
an increase in BPG may result in a rightward shift on the curve only at altitude exposure, and is NOT a major cause of rightward shift during sea level exercise

64
Q

if you are dropping off more O2 to the tissues, what happens to (a-v)O2 difference and VO2

A

increases (a-v)O2 difference (due to decreased venous return) which will increase VO2

65
Q

how is O2 transported in muscle

A

via myoglobin

66
Q

myoglobin

A

shuttles O2 from the cell membrane to the mitochondria of skeletal and cardiac muscle fibers

67
Q

what type of skeletal muscle fiber contains high Mb content

A

type 1 fibers

low in type IIx fibers

68
Q

what has a higher affinity for O2 : Mb or Hb

A

Mb because it binds O2 at a very low PO2

69
Q

when Hb is unloading on the dissociation curve what is happening with Mb

A

loading

70
Q

Mb O2 stores serve as an ___ from rest to exercise

A

“O2 reserve” during transition periods from rest to exercise

71
Q

after exercise, Mb O2 stores must be

A

replenished and this O2 consumption above rest contributes to O2 debt (EPOC)

72
Q

how is CO2 transported in blood

A

10% dissolved CO2 in plasma
20% bound to Hb
70% as bicarb (HCO3-)

73
Q

bicarb buffering reaction

A

CO2 + H2O = H2CO3 = HCO3- + H+

74
Q

CO2 transport in the blood

A

CO2 produced in high concentrations from Krebs cycle
CO2 dissolved in plasma (10%)
CO2 combines with Hb (20%)
CO2 bound to Hb converted to carbonic acid which turns into bicarb. for the reaction to continue, need to shuttle bicarb out and chloride in to drive the formula to the left

75
Q

pulmonary ventilation does what to bicarb rxn

A

removes H+ from blood by HCO3- reaction and exhales out CO2 (rxn driven to the left)

76
Q

increased ventilation results in

A

CO2 exhalation which reduces the PCO2 and H+ concentration to increase pH via hyperventilation

77
Q

decreased ventilation results in

A

buildup of CO2 via increases in PCO2 and H+ concentration which decreases pH and activates respiratory control centers

78
Q

at the onset of submaximal, steady state exercise what happens to PO2, PCO2, and ventilation

A

PO2 and PCO2 remain unchanged
Ventilation increases rapidly then a slower, steady rise towards steady state in order to expire more CO2 and bring in more O2

79
Q

what happens to PCO2 and ventilation during prolonged exercise in a hot environment

A

little change is observed but ventilation is still increased due moving anatomical dead space, NOT the increase in PCO2

ventilation tends to drift upward b/c increased blood temp activates respiratory control center for thermoregulation

80
Q

VT

A

inflection point where Ve increases exponentially

increase in ventilation is to meet the bodies needs to exhale excess CO2 to help balance the change in CO2 or H+ ions

81
Q

is the pulmonary system a limitation during submax exercise

A

no because we can maintain arterial PCO2 throughout submax exercise to max exercise

82
Q

arterial PO2 is maintained within

A

10-12 mmHg of resting value

83
Q

does the pulmonary system limit performance in a trained subject during during graded exercise

A

pulmonary system may limit performance in highly trained elite endurance athletes during maximal exercise due to

mechanical limitations of the lung (if maintaining a high ventilation during max exercise= increase respiratory muscle fatigue or shuttling too much blood flow to respiratory lungs/muscles which will limit performance by taking O2 away from legs)

respiratory muscle fatigue during prolonged (>120min), high intensity (90-100% VO2 max) exercise

40-50% athletes experience exercise induced arterial hypoxemia

84
Q

why do elite athletes experience a decrease in arterial PO2 during high intensity exercise

A

blood flowing too quickly across the lungs (pulmonary capillary transit time) - less than 0.25 sec

85
Q

typical Ve value at rest and at max exercise

A

rest- 7.5 L/min
max- 120-175 L/min

86
Q

typical f value at rest and max exercise

A

rest- 15 breaths/min
max- 40-50 breaths/min

87
Q

typical Vt value at rest and max exercise

A

rest- 0.5 L/breath
max- 3-3.5 L/breath

Exercise Physiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions