Brainscape's Knowledge GenomeTM

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


See full index

Resp - mine > Physiology > Flashcards

Physiology Flashcards

1
Q

what is internal respiration

A

intercellular mechanisms which consume CO2 and produce O2

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

what is external respiration

A

the sequence of events that lead to the exchange of CO2 and O2 between the external environment and the body cells

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

how many steps are involved in external respiration and what are they

A

four:

  1. ventilation
  2. exchange of O2 and CO2 between air in alveoli and blood
  3. transport of O2 and CO2 between lungs and tissue
  4. exchange of O2 and CO2 between blood and tissues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what type of blood is involved in the 4th step of external respiration

A

systemic (capillaries)

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

what type of blood is used in the 3rd step of external respiration

A

circulating

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

where is the blood is used in the 2nd step of external respiration

A

pulmonary capillaries

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

what 3 pressures are important for ventilation

A
  1. atmospheric
  2. intra-alveplar
  3. intrapleural
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

explain ventilation via pressures

A

air moves from high to low pressure (due to boyles law). During inspiration the muscles will contract resulting in an increased volume causing the gas pressure (and intra-alveolar pressure) to decrease, this causes the air to move into the lungs until the intra-alveolar pressure = atmospheric pressure

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

what is boyles law

A

at any constant temperature the pressure exerted by a gas varies INVERSELY with the volume of the gas

“as the volume increases, the pressure will decrease”

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

how do the lungs adhere to the chest wall, what does the adherence cause

A
  1. intrapleural fluid cohesiveness = water molecules in the intrapleural fluid are attracted to each other and resit being pulled apart
  2. negative intrapleural pressure = intrapleural pressure is lower than atmospheric and intra-alveolar this causes the lungs to push out and the chest wall to push in and results in them sticking together

these 2 factors result in the lungs expanding when the chest wall does

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

identify the muscles used in inspiration (under normal conditions)

A
  1. diaphragm (main)

2. intercostal muscles

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

what type of expansion do the intercostal muscles allow

A

horizontal

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

what type of movement does the diaphragm allow

A

vertical

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

is inspiration active or passive

A

active, energy is needed to contract the muscles

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

is expiration active or passive

A

passive

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

what causes the lungs to recoil

A
  1. elastic connective tissue

2. alveolar surface tension

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

what is alveolar surface tension

A

attraction between the water molecules at liquid air interface, produces A LOT of force

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

what is surfactant and what secretes it

A

mixture of lipid and proteins secreted by type 2 alveoli

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

what is the role of surfactant

A

reduces surface tension by interspacing between water molecules, it acts more on smaller alveoli

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

what alveoli are at risk of collapse, what law is this

A

smaller alveoli, LaPlace’s law

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

what prevents collapse of alveoli (3)

A
  1. surfactant
  2. alveolar independence
  3. transmural pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is alveolar independence

A

if a alveoli begins to collapse then surrounding alveoli will stretch then recoil reopening the collapsed alveoli

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

what is tidal volume (TV) and what is the average volume

A

volume of air entering or leaving the lungs during a single breath
0.5L

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

what is inspiratory reserve volume (IRV) and what is the average volume

A

extra volume of air that can be MAXIMALLY inspired over and above the typical resting tidal volume
3L

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

what is expiratory reserve volume (RV) and what is the average volume

A

extra volume of air that can be ACTIVELY expired by maximal contraction beyond the normal volume of air after a resting tidal volume
1L

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

what is residual volume (RV) and what is the average volume

A

minimum volume of air remaining in the lungs even after a maximal expiration
1.2L

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

what is inspiratory capacity (IC) and what is the average volume

A

maximum volume of air that can be inspired at the end of a normal quiet expiration
3.5L

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

what 2 volumes make the inspiratory capacity

A

IC = IRV + TV

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

what is functional residual capacity (FRC) and what is the average volume

A

volume of air in lungs at the end of normal passive expiration
2.2.L

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

what 2 volumes make the functional residual capacity

A

FRC = ERV +RV

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

what is vital capacity (VC) and what is the average volume

A

maximal volume of air that can be moved out during a single breath following a maximal inspiration
4.5L

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

what 3 volumes make up vital capacity

A

VC = IRV + TV + ERV

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

what is total lung capacity (TLC) and what is the average volume

A

total volume of air that the lugs can hold

5.7L

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

what 2 volumes make up total lung capacity

A

TLC = VC + RV

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

what are the accessory muscles of inspiration

A

sternocleidomastoid

scalenus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what are the muscles of active respiration

A

internal intercostal muscles

abdominal muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what lung volumes & capacities can’t be measured by spirometry

A

residual volume

total lung capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what does the volume time curve in spirometry allow you to determine

A

forced vital capacity (FVC)
forced expiration in 1 second (FEV1)
FEV1/FVC ratio

together all three are known as “dynamic lung volumes”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what are the dynamic lung volumes in obstructive lung disease

A

FVC = normal
FEV1 = reduced
FEV1/FVC ratio = reduced (>70%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what are the dynamic lung volumes in restrictive lung disease

A

FVC = reduced
FEV1 = reduced
FVC/FEV1 ratio = normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what is “work of breathing”

A

the energy required to breathe (normally 3% of total energy expenditure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

when is work of breathing increased (4)

A
  1. DECREASED pulmonary resistance
  2. DECREASED elastic recoil
  3. INCREASED airway resistance
  4. INCREASED need for ventilation (e.g. exercise)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

when is residual volume increased (give examples)

A

when elastic recoil of the lung is lost e.g emphysema, old age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what is forced vital capacity (FVC)

A

maximum volume that can be forcibly expelled from the lungs following a maximum inspiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what is forced expiratory volume in 1 second (FEV1)

A

volume of air that can be expired during the first second of expiration in FVC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

examples of OBSTRUCTIVE lung disease

A

asthma

COPD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

examples of RESTRICTIVE lung disease

A

fibrosis

interstitial lung disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what factors influence airway resistance

A 
airway radius (primary determinant)
disease states (e.g. asthma, COPD)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

how is airway radius altered

A

parasympathetic stimulation = bronchoconstriction

sympathetic stimulation = bronchodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is lung compliance

A

measure of the effort required to stretch or distend the lungs
aka volume change per unit of pressure across the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

low compliance results in _______ work required

A

High

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

high compliance results in _______ work required

A

low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

what causes increased compliance

A

loss of elastic recoil (e.g emphysema)

age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

what causes decreased compliance

A 
fibrosis
oedema
lung collapse
pneumonia
absence of surfactant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

what does increased compliance result in

A

patients have to work harder to get the air out of their lungs
hyperinflation

56
Q

what does decreased compliance result in

A

greater pressure change is needed to produce a change in volume
SOB on exertion

57
Q

what type of spirometry pattern can decreased compliance cause

A

restrictive

58
Q

what causes dynamic airway compression

A

rising pleural pressure during active expiration

59
Q

what does dynamic airway compression cause in normal people

A

increased pressure upstream in the airway which helps to open the airway by increasing driving pressure between the alveolus and the airway

60
Q

what does dynamic airway compression cause in an obstruction

A

driving pressure between the alveolus and airway is lost leading to a fall in airway pressure downstream. This results in airway compression causing airway collapse

61
Q

what is pulmonary ventilation

A

the volume of air breathed in and out per min

= tidal volume x RR

62
Q

what is alveolar ventilation

A

the volume of air exchanged between the atmosphere and alveoli permit

= (tidal volume - dead space volume) x RR

63
Q

why is alveolar ventilation lower than pulmonary ventilation

A

because of the presence of anatomical dead space

64
Q

what is anatomical dead space

A

airways which are not available for gas exchange but which still contain some inspired air

65
Q

how is pulmonary ventilation increased. which method is more effective and why

A

increase depth (tidal volume) of breathing and rate of breathing (RR)

depth is more effective due to dead space

66
Q

what does the transfer of gases between the body and the atmosphere depend on

A

ventilation and perfusion

67
Q

what is ventilation

A

the rate at which GAS is passing through the lungs

68
Q

what is perfusion

A

the rate at which BLOOD is passing through the lungs

69
Q

what is alveolar dead space

A

ventilated alveoli which are not adequately perfused with blood

70
Q

what is physiological dead space

A

alveolar dead space + anatomical dead space

71
Q

what matches airflow to blood flow

A

local control of airway smooth muscle and arterioles

72
Q

what is the result of increased perfusion

A

accumulation of CO2 in alveoli which will decrease airway resistance via airway dilatation leading to increased airflow (ventilation)

73
Q

what is the result of increased ventilation

A

increase in alveolar O2 concentration which will cause pulmonary vasodilatation leading to increased blood flow (perfusion)

74
Q

what is the effect of decreased and increased O2 on pulmonary arterioles

A 
decreased = vasoconstriction
increased = vasodilation
75
Q

what is the effect of decreased and increased O2 on systemic arterioles

A

decreased = vasodilation

increased =vasoconstriction

76
Q

what factors influence the rate of gas exchange across the alveolar membrane

A
  1. partial pressure gradient of O2 and CO2
  2. diffusion coefficient for O2 and CO2
  3. surface area of alveolar membrane
  4. thickness of alveolar membrane
77
Q

what is partial pressure and what does it determine

A

it is the pressure that a gas would exert if it occupied the total volume of the mixture without the other gases

it determines the pressure gradient

78
Q

what would a big gradient between the partial pressure of oxygen in the alveolar air and the oxygen in the arterial blood indicate

A

problems with gas exchange or a L to R shunt in the heart

79
Q

what is the diffusion coefficient

A

solubility of a gas in membranes

80
Q

compare the diffusion coefficient of CO2 and O2 and give an explanation for it

A

CO2>O2 by quite a bit to make up for the difference in partial pressure

81
Q

compare the partial pressures of CO2 and O2

A

O2>CO2 by quite a bit

82
Q

explain the effects of membrane surface area on gas transfer

A

Large surface area = fast transfer

83
Q

explain the effects of membrane thickness on gas transfer

A

thick membrane = slow transfer

84
Q

what are alveoli

A

thin-walled inflatable sacs

85
Q

describe alveoli (walls & encirclement)

A

walls concept of a single layer of flattened type 1 alveolar cells each encircled by a pulmonary capillary with a narrow interstitial space

86
Q

how is O2 carried in the blood

A
  1. dissolved (tiny amount)

2. bound to haemoglobin

87
Q

what is the MAIN method of O2 transport within the blood

A

bound to haemoglobin

88
Q

describe the binding of O2 to haemoglobin

A

reversible

89
Q

describe haemoglobin (Hb)

A

4 harm groups, each one can bind to a O2

90
Q

what is the primary factor which determines % saturation of Hb with O2

A

partial pressure of O2 (PO2)

91
Q

what type of curve is theO2-Hb dissociation curve

A

sigmoidal

92
Q

what is oxygen delivery index due to

A

CO x O2 conc of arterial blood

93
Q

what is O2 concentration of arterial blood determined by

A

concentration of Hb in the blood

% saturation of Hb with O2

94
Q

what is O2 delivery to the tissues affected by

A
  1. DECREASED PO2
  2. respiratory diseases
  3. anaemia
  4. Heart failure
95
Q

what is the Bohr effect

A

RIGHT shift of Hb-O2 curve causing increased release of O2 at the tissues

96
Q

what causes the Bohr effect

A

INCREASED:

  1. PCO2
  2. [H+]
  3. temperature
  4. 2,3-biphosphoglycerate
97
Q

how does foetal Hb differ from adult Hb

A

structure: has 2 alpha units and 2 gamma units (instead of 4 alpha) causing less interaction with 2,3-biphosphoglycerate
affinity: has a higher affinity for O2

98
Q

what effect does foetal Hb have on the dissociation curve

A

shifts to the LEFT

99
Q

why does foetal Hb have a higher affinity for O2 than adult Hb

A

to allow O2 transfer from the mother to the foetus even if the PO2 is low

100
Q

describe the myoglobin curve

A

hyperbolic

101
Q

what does the presence of myoglobin indicate

A

muscle damage

102
Q

what does myoglobin do

A

it releases O2 at a very LOW PO2

it provides short term storage for O2 at anaerobic conditions

103
Q

how is CO2 carried in the blood

A
  1. in solution (10%)
  2. as bicarbonate
  3. carbamino compounds
104
Q

describe the process of CO2 transport through the blood as a bicarbonate

A

this process occurs in RBC

water reacts with CO2 to from carbonic acid which dissociates into a H+ ion and a bicarb ion

105
Q

describe the process of CO2 transport through the blood as a carbamino compound

A

formed by the combination of CO2 with terminal amine groups in blood proteins
very RAPID formation (even without enzymes)

106
Q

how is the MAJORITY of CO2 transported in the blood

A

as a bicarbonate

107
Q

what is the Haldane effect

A

removing O2 from Hbincreases the ability of Hb to pick up CO2 and H+ generated by CO2

108
Q

how does the Bohr and Haldane effect work together

A

they work in SYNCHRONY to facilitate O2 liberation and uptake of CO2 and H+ generated by CO2 at tissues

109
Q

How is CO2 liberation at the lungs facilitated

A

Hb picks up O2 at the lungs which WEAKENS its ability to bind to CO2 and H+ generated by CO2

110
Q

state the location of the respiratory centres and their function

A 
medulla = major rhythm generator 
pons = neurones here modify the rhythm
111
Q

what happens when the pneumatic centre is stimulated

A

inspiration is terminated

112
Q

what causes pneumatic centre stimulation

A

dorsal respiratory neurones firing

113
Q

what is the role of the pneumatic centre

A

prevents breathing becoming prolonged inspiratory gasps with brief expiration

114
Q

how is inspiration terminated

A

pneumatic centre is stimulated by dorsal neurones firing

115
Q

how is inspiration prolonged

A

apneustic centre is stimulated leading to excitement of inspiratory area of the medulla

116
Q

what does apneustic centre stimulation cause

A

excitement of inspiratory are of medulla causing prolonged inspiration

117
Q

where is the rhythm of breathing generated

A

medulla

118
Q

where is the rhythm of breathing modified

A

pons

119
Q

how is active breathing established (role that neurones play)

A

increased firing from dorsal neurones excites a second group of ventral respiratory group neurones which excites the internal intercostal and abs to create forceful expiration

120
Q

how is tidal breathing established (role that neurones play)

A

pre-botzinger complex generates the rhythm, dorsal respiratory group neurones are excited and fire in bursts which causes contraction of inspiratory muscles. (inspiration)

when firing stops, the muscle relaxes (passive expiration)

121
Q

what is the rhythm generated by (_____ complex)

A

pre-botzinger complex

122
Q

what external stimuli are capable of influencing the respiratory centres

A

higher brain centres = cerebral cortes, limbi system, hypothalamus
stretch/joint/baro- receptors

123
Q

what role do stretch receptors play in breathing

A

prevent over-inflation of lungs

124
Q

what role do joint receptors play in breathing

A

detect change in movement which will cause a change in ventilation required

125
Q

what role do baroreceptors play in breathing

A

decreased BP results in increased ventilatory rate

126
Q

where are the peripheral chemoreceptors located

A

on carotid bodies at carotid bifurcation

on aortic bodies on the superior aspect of the arch of the aorta

127
Q

where are the central chemoreceptors located

A

near the surface of the medulla

128
Q

what are the central chemoreceptors stimulated by

A

[H+] of the cerebrospinal fluid

129
Q

what are the peripheral chemoreceptors stimulated by

A

tension of O2 and CO2 in blood

[H+] in blood

130
Q

what are the acute responses to hypoxia

A

hyperventilation

increased CO2

131
Q

what are the chronic adaptions to hypoxia

A 
increased RBC production
increased2,3-BPG production
increased number of capillaries
increased number of mitochondria 
kidneys conserve acid
132
Q

how would a rise in arterial [H+] effect ventilation

A

ventilation would increase (acid-base balance)

133
Q

how would a drop in arterial [H+] effect ventilation

A

ventilation would decrease (acid-base balance)

134
Q

how would a severe drop in arterial PO2 effect ventilation

A

severe hypoxia depresses respiratory centre causing decreased ventilation

135
Q

how would a drop in arterial PCO2 effect ventilation

A

ventilation would increase (acid-base balance)

Resp - mine (18 decks)

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