Brainscape's Knowledge GenomeTM

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


See full index

BDS Stage 1 > New RS > Flashcards

New RS Flashcards

1
Q

What are the main functions of the respiratory system ?

A 
Gas exchange
hormone production 
protection from pathogens 
regulation of body pH 
vocalisation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do you calculate surface tension ?

A

0.5(pressure x radius of alveoli)

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

As a percentage of vital capcity what is the normal FEV of a healthy person ?

A

more than 70%`

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

What does it mean if perfusion limited ?

A

not enough blood to carry away oxygen
rapid transfer of oxygen from the alveolus to the capillaries
equilibrium reached before the end of the capillary bed

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

What are the factors that affect gas exchange in the lungs ?

A

surface area
thickness of the membrane
pressure gradient
solubility of gas

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

Why would HPV be taking place in birth ?

A

lungs are hypoxic until birth

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

How can COPD trigger HPV ?

A

COPD can cause a decrease in ventilation - leads to HPV - increases pulmonary pressure

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

What causes dissociation of oxgen from Hb ?

A

low partial pressure of oxgen reduces the affinity of Hb for o2- dissociation

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

In what conditions would 2.3 DPG be produced ?

A

exercise
anaemia
high altitudes
lung didease

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

What is the purpose of the chloride shift ?

A

maintain the membrane potential between erythrocyte and blood

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

How do central chemoreceptors measure changed in carbon dioxide production ?

A

Carbon dioxide diffuses from the cerebral capillaries into the CSF
reaction with water leads to proton and bicarbonate production
protons bind to the central chemoreceptors in the floor of the IVth ventricle
trigger an increase in VR

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

What effects does the autonomic system have on the lungs ?

A

mucus secretion
vasoconstriction
bronnchodilation

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

What is cheynes stokes respiration ?

A

partial pressure of oxygen and carbon dioxide never stabilises
due to delay in blood reaching the peripheral chemoreceptors
lungs alternate between deep fast breathing and shallow breathing

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

How does venous and arterial oxygen change during exercise ?

A

venous oxygen drops

arterial oxygen is stable

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

What does high altitude trigger ?

A

hypoxic ventilatory response

hyperventilation

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

How does hyperventilation alter pH ?

A

decrease in carbon dioxide

alkalosis

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

How is blood and CSF pH normalised after 3 days ?

A

bicarbonate transported out the of the CSF into the blood
central chemoreceptors reset
bicarbonate taken cre by the kidney

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

What are the functions of the lower respiratory tract ?

A

conduct air
gas exchange
regulate flow

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

What is the structure of alveolar cells type 1 ?

A

single cell thick
side facin the blood has holes- leaky
side facing the lung is strengthened with collagen fibres

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

How can bronchiole diameter be regulated ?

A

parasympathetic- Ach acts on M3 receptors- bronchoconstriction
Symapthetic- Noardrenaline- bronchodilation- Beta 2 receptors

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

What is poiuselles law ?

A

change in pressure/ r4

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

What affects airway resistance ?

A

viscosity

turbulent or lamina flow

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

Which structures have the highest resistance ?

A

bronchi

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

How are the first ribs joined to the manubrium ?

A

synchondroses

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

How do you work out pressure ?

A

2 X st/radius

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

What is the size of dead space ?

A

150 ml

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

What is the physiologic dead space ?

A

anatomic + alveolar dead space

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

How is diffusion capacity optimised ?

A

shape of type 1 alveolar cells

fusion of the alveoli with the basement membrane

29
Q

Describe a perfusion limited scenario ?

A

not enough blood to carry away oxygen
rapid transfer of gas between alveoli and the blood
equilibrium reached before the end of the capillary bed

30
Q

What are the perfusion limited gases ?

A

N20 and O2

31
Q

What does the perfusion graph show ?

A

p cap on the side

palv on bottom

32
Q

Describe a diffusion limited scenario ?

A

Slow transfer of gas between the alveoli

equilibrium not reached in transit time

33
Q

What is a diffusion limited gas ?

A

CO

34
Q

What happens in emphysema ?

A

alveoli are ruptured
reduced FEV
loss of elastin and connective tissue

35
Q

What are the conditions at the apex ?

A

V>Q
High pH
Alveoli squeeze capillaries

36
Q

What are the conditions at the base ?

A

Q>V
low hydrostatic pressure to overcome
low pH

37
Q

How can you assess perfusion using Xe 133 ?

A

Inject into blood
pooly soluble so it leave via the lungs
poorly perfused- fainter - apex

38
Q

What does a pulmonary embolus do ?

A

blocks perfusion
no gas transfer
fainter stain

39
Q

What happens in HPV ?

A 
Reduced oxygen in the alveolus and therefore gradient 
blood not fully oxygenated 
HPV
blood diverted to well ventilated areas
V/Q match
40
Q

How is COPD linked to HPV ?

A

COPD means less oxygen in the blood
triggers HPV
increase in pulmonary pressure
leads to right ventriculr heart failure and pulmonary oedema

41
Q

What does Hb also bind to ?

A

Protons
CO
NO

42
Q

What does NO bind to ?

A

cysteine residues

vasodilator

43
Q

How is co2 transported ?

A

70% in bicarnbonate buffer system
23% bound to N terminus
7% soluble

44
Q

What is the bicarbonate buffer system ?

A

Carbon dioxide diffuses into capillaries
reacts to water to form carbonic acid and protons and bicarb
Excess bicarb which shifts equilibrium
so in the blood bicarb leaves the RBC and chloride replaces it
in the lung chloride leaves the RBC and Bicarb enters so the reaction can happen in reverse
Co2 released in the lungs

45
Q

What is the bohr effect ?

A

protons reduces the affinity of Hb for O2

46
Q

What is the haldane effect ?

A

Carbon dioxide reduces Hbs affinity for O2

47
Q

What potentiates the O2 response ?

A

low O2 and high Co2/low pH

48
Q

What do glomus cells signal through ?

A

IX

49
Q

How is low oxygen detected by peripheral chemoreceptors ?

A 
Low oxygen in blood
K channels close
cell depolarises 
Ca enters through Ca channels 
exocytosis of dopamine vesicles 
bind to dopamine receptors
signal through IX
50
Q

What does decreasing alveolar co2 do ?

A

potentiate the response

51
Q

What is the BBB impermeable to ?

A

protons and bicarb

52
Q

What is the effect of consciosuness on HR ?

A

during unconsciousness we tolerate more carbon dioxide
less sensitive
in a heroin overdose - less sensitive and autonomous activity is not stimulated enough

53
Q

Where are the pulmonary stretch receptors located ?

A

airways

visceral pleura

54
Q

What is the output of DRG ?

A

phrenic

55
Q

What does the VRG contain ?

A

mixture of ins and exp neurones exp at the end

56
Q

What is the pre botzinger complex ?

A

collection of insp neurones in the VRG

generate basic rhythm

57
Q

What is forced expiration controlled by ?

A

pre botzinger complex

58
Q

What is the voluntary control system ?

A

cerebral cortex
to the RC in medulla
output to the respiratory muscles

59
Q

What is the involuntary system ?

A

limbic system- emotional response

hypothalamus- temperature regulation

60
Q

What are the changes to ventilation during exercise ?

A

increase in TV
increase in VR
more capillaries
increased diffusion capacity

61
Q

What are the stimulants of pulmonary ventilation in exercise ?

A

initially- neural - primary motor cortex
Increased K
muscle spindle and proprioceptors

62
Q

What are eh consequences of hyperventilation ?

A

remove co2
alkalosis
increased affinity of Hb for O2
Reduced VR

63
Q

How can pulomoanry oedema happen in hypoxic cinditions ?

A

HPV
increased pulmoanry pressure
high hydrostatic pressure
balance between hydrostatic and oncotic pressure diturbed

64
Q

What are the long term adaptation to high altitude ?

A 
bicarbonate transported out of the CSF
reduced CSF pH 
resets the central chemoreceptors
Bicarbonate taken care by the kidneys
central more sensitive
65
Q

What happens in sustained hypoxia ?

A

2,3 DPG made in the RBCs
curve shifts to the right- facilitate oxygen release
peritubular cells in the kidney detect low oxygen- release EPO - RBC synthesis increased- increased oxygen carrying capacity
heart has to pump more due to increased viscosity of the blood

66
Q

How do gangrene and frostbite occur ?

A

vasoconstriction of peripheral arteries

in low temperatures

67
Q

What is average arterial co2 pressure ?

A

40 mmHg

68
Q

What do peripheral chemoreceptors sense ?

A

oxygen below 60 mmHg

BDS Stage 1 (39 decks)

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