lecture 15 Flashcards
(126 cards)
1
Q
respiration steps (3)
A
pulmonary ventilation
external respiration
internal respiration
2
Q
pulmonary ventilation
A
gas exchange between atmosphere and lung tissues
3
Q
external respiration
A
gas exchange between lung tissues and blood
4
Q
internal respiration
A
gas exchange between blood and body tissues
5
Q
functions of respiratory system (3)
A
exchange gases
regulate blood pH
permits phonation (vocal sounds)
sense of smell, filters air
6
Q
oto(rhino)laryngology
A
the study of the respiratory system
7
Q
why do cells need o2?
A
aerobic cellular respiration (acts as terminal receptor) = ATP
8
Q
upper respiratory system parts
A
nose, nasal cavity, pharynx, associated structures
9
Q
lower respiratory system parts
A
larynx, trachea, bronchi, lungs
10
Q
two zones of respiratory system
A
conducting zone
respiratory zone
11
Q
conducting zone
A
directs air toward the respiratory zone
filters, warms, humidifies air as it enters the body
12
Q
respiratory zone
A
site of gas exchange
includes respiratory bronchioles, alveolar sacs and ducts
13
Q
the nose
A
made of bone , cartilage, and CTs
contains nasal cavity and external nares
14
Q
air enters the nose through;
A
teh external nares
15
Q
nasal cavity
A
contains paranasal sinuses, nasal conchae, and olfactory epithelium
16
Q
nasal septum function
A
divide nasal cavity in 2
17
Q
olfactory epithelium (where, goblet cells? cilia?)
A
located in the nasal cavity
ciliated with no goblet cells
18
Q
pharynx
A
- tube of skeletal muscle lined with a mucous membrane
- starts at internal nares and ends at cricoid cartilage
3 subdivisions
19
Q
3 subdivisions of the pharynx
A
nasopharynx
oropharynx
laryngopharynx
20
Q
nasopharynx (tissue and function)
A
ciliated pseudostratified columnar epi
sweeps mucus into pharynx
21
Q
oropharynx
A
non keratinized stratified squamous epi
- contains fauces
- passageway for air and food
- contains tonsils
22
Q
function of the tonsils
A
facilitate immune response
23
Q
tonsils (3)
A
pharyngeal tonsil
palatine
lingual
24
Q
laryngopharynx
A
basically the same as oropharynx but lower
25
thyroid cartilage
hyaline cartilage that forms anterior surface of the larynx
(adams apple)
26
epiglottis
flap of elastic cartilage that covers the trachea during swallowing
27
cricoid cartilage
ring of hyaline cartilage that makes up the inferior wall of larynx
- landmark for tracheotomies
28
true vocal cords
aka vocal folds
non keratinized stratified squamous epi
- form elastic ligaments
29
false vocal cords
aka vestibular folds
come together when breath is held
30
trachea
has 16-20 rings of hyaline cartilage to keep it patent (from collapsing)
- lined with ciliated pseudostratified epi
31
bronchi
split off of trachea (left and right bronchus)
- branch into the lungs as narrowing pathways
32
carina
ridge at the branchpoint of the trachea
33
how do the mucous membranes change throughout the bronchiole tree?
list tissues
the tissues get thinner and thinner
ciliated pseudostrat
ciliated simple cuboidal
nonciliated simple cuboidal -
simple squamous - alveolar sacs
34
pleural membrane
two serous membranes (parietal/visceral?)
- pleural cavity - space between
secretes pleural fluid
35
function of the pleural fluid
reduce friction and provides surface tension
36
inferior portion of the lungs
base
37
superior portion of the lungs
apex
38
mediastinal surfaces (2)
hilum
cardiac notch
39
hilum
mediastinal surface
- permits passage of the bronchi, blood vessels, nerves, and lymph vessels
40
cardiac notch
mediastinal surface
- provides space for the heart
- decreases left lung relative to right by 10%
41
fissures
divide lungs into lobes
42
oblique fissure
separates inferior and superior lobes
43
horizontal fissure
borders middle lobe and superior lobe on right lung only
44
lobar bronchi names
based on what lobe they branch into
superior lobar bronchus
middle (right only)
inferior
45
lobar bronchi branch into:
segmental bronchi
46
bronchopulmonary segment
13 in right, 8 in left
- damaged segments can be removed without disturbing others
47
lobules
smaller components of bronchopulmonary segments consisting of:
- branch of terminal bronchi
- arteriole/venule
- lymphatic vessel
all of these are wrapped in elastic CT
48
respiratory bronchioles
microscopic bronchial branches
- simple cuboidal epi
- branch into alveolar ducts
49
alveoli
air sacs where pulmonary and external respiration occur
50
type 1 alveolar cells
simple squamous epi
thinness facilitates gas exchange
51
type 2 alveolar cells
nonciliated cuboidal epi at the septa between alveoli
- secrete surfactant that prevents alveolar walls from sticking together
52
respiratory membrane
very thin - 0.5 micrometres
liens alveoli and associated capillaries
4 layers
53
layers or respiratory membrane (superficial to deep)
alveolar wall - type 1/2 cells + macrophages
epithelial basement membrane
capillary basement membrane
capillary endothelium - contacts blood
54
pulmonary arteries
bring deoxy blood from heart to be oxy
- constrict in response to hypoxia
- responsible to ventilation-perfusion coupling
55
ventilation perfusion coupling
if ventilation is high in a segment, perfusion will be high as well
this ensures that only healthy lung tissues are maximally used
56
bronchial arteries
branch from aorta
deliver oxy blood to muscular tissue of the lungs
57
patency
the ability of a passageway to remain unobstructed
58
just before inhalation, pressure inside the lungs is _______ to atmospheric pressure
equal
59
gases move from ______ to _____ partial pressure
high to low
60
for inhalation to occur, pressure must be ______
below atmospheric pressure
61
partial pressure
the pressure a gas exerts on its surroundings
62
boyles law
states that the pressure inside a container is inversely proportionate to the volume of that container
63
to decrease the pressure in the lungs (to inhale air) we can:
increase the volume of the lungs
64
how much does the diaphragm depress?
normal inhalation - 1cm
strenuous - up to 10
65
what is responsible for the % of air inhaled? (2)
75% - depression of diaphragm
25% - external intercostal muscles
66
intrapleural pressure
ensures lung tissue expands during inhalation
- negative pressure within thoracic cavity
- keeps pleural membrane suctioned to thoracic cavity wall, so when the cavity expands, the lungs do too
67
is inhalation active or passive process
active
68
is exhalation active or passive process
passive
69
active exhalation
during vigorous exercise or playing a wind instrument
70
pleural effusion
accumulation of pleural fluid in the pleural cavity
- leads to decreased lung volume
71
compliance
distensibility of elastic tissues
72
air resistance is determined by:
airway diameter
obstruction of airways (like in COPD)
73
COPD
chronic obstructive pulmonary disorder
74
lung volumes
a specific measure of air inhaled, exhaled, or stored
75
lung capacity
sums of specific lung volumes
76
spirometer
used to measure lung volumes
77
carbon is _____X more soluble in water than O2
24x
therefore there is more CO2 in blood plasma than O2
78
why is the partial pressure of O2 in alveoli even lower than at rest during exercise?
because we are using lots of it, and so we can take in more of it
79
what maximizes oxygenation of blood
slow movement of blood through capillaries
80
why do tissue cells constantly produce CO2, and what does it result in
as a waste product of aerobic respiration
results in constantly higher partial pressure of CO2 outside capillaries, because CO2 moves from tissues to the blood, down its C gradient
81
factors affecting respiration (4)
- partial pressure gradient of gas
- surface area over which gas is exchanged
- diffusion distance
- solubility of gas / molecular weight
82
how does partial pressure gradients of gas affect respiration?
pressure gradient is needed to allow gas to move in and out of the lungs
(eg. at high altitudes, pressure is lower, making the pressure inside and outside the lungs closer. leads to slower respiration - altitude sickness)
83
how does surface area over which gases are exchanged affect respiration?
more contact with gases to be exchanges = higher rate of diffusion
(eg. alveolar surface area is massive to allows efficient gas exchange)
84
how does diffusion distance affect respiration
shorter distance = more efficient diffusion
(eg. thin alveolar walls = shorter distance for gas to move)
85
how does solubility of gas/molecular weight affect respiration
O2 weighs less, but CO2 is more water soluble.
this means you will run out of O2 faster than you will accumulate excess CO2
86
how is O2 transported (percentages)
98.5% - hemoglobin
1.5% - dissolved in blood plasma
87
how is the binding and dissociation of O2 to/from hemoglobin summarized (reaction)
Hb + O2 --> Hb - O2
88
what affects the saturation of hemoglobin? (6)
partial pressure of O2
blood acidity
Partial pressure of CO2
temperature
products of glycolysis
types of hemoglobin
89
how does partial pressure of O2 affect the saturation of hemoglobin?
higher the pressure (mmHg), the closer Hemoglobin is to being saturated
between 60-100 mmHg, hemoglobin is almost 100% saturated, which is why external respiration is so effective (average atmospheric pressure - 760mmHg)
90
graph drawing for final - what are the x and y axis names?
x - partial pressure of O2 (Po2 (mmHg))
y - percent saturation of hemoglobin
91
blood pH graph lines
superior line -
middle line -
inferior line -
which is which?
superior line - higher blood pH
mid - normal blood pH
inferior line - low blood pH
92
why might increased percent saturation of hemoglobin be a bad thing?
if Hb bind too well to O2 (like in higher pH, low PCo2, or low temp) O2 will be less reversible, and Hb wont let go of it
93
affinity
the tendency for a substance to bind another
94
how does affinity for O2 affect saturation of Hb?
the affinity of Hb is affected by acidity and PCo2
95
most CO2 is transported as _____ in blood plasma
H2CO3
96
blood PCo2 graph lines
superior -
mid -
inferior -
which is which?
remember, low PCo2 = higher pH
superior - low PCo2
mid - normal
inferior - High PCo2
97
blood temperature graph lines
superior -
mid -
inferior -
which is which
superior - low temp
mid - normal
low - higher temp
98
how does temperature affect affinity for Hb to bind O2?
skeletal muscle generates heat, which favours release of o2 to tissues
99
how does temperature affect affinity of Hb for O2
skeletal muscle produces heat which heats the blood and favours the release of O2 to tissues
100
how do the products of glycolysis affect the affinity of Hb for O2?
one product (BPG) binds Hb and changes it structure, decreasing its affinity
101
how does the type of Hb affect its affinity for O2?
fetal Hb (Hb-F) can bind up to 30% more O2 than adult Hb (Hb-A)
102
how is CO2 transported in the body? (%)
7% - dissolved in blood plasma as CO2
23% - bound to protein to form carbamino compounds (Hb+CO2 = carbaminohemoglobin)
70% - transported as bicarbonate
103
bicarbonate reaction (carbonic acid dissociation)
CO2 + H2O <-> H2CO3 <-> H+ HCO3
104
chloride shift ensures:
that erythrocytes maintain electrical balance
105
chloride shift
when HCO3 diffuses out of the cell from high to low concentration in plasma, and Cl- ions diffuse into the cell to restore ion homeostasis in RBCs
106
reverse chloride shift ensures:
that CO2 can be eliminated at the pulmonary capillaries
107
reverse chloride shift reaction
HCO3 + H -> H2CO3 -> H2O + CO2
108
reverse chloride shift
turns bicarbonate back into CO2 to be exhaled. as HCO3 decreases, Cl moves out of cells
109
where does the chloride shift happen
at systemic capillaries
110
where does teh reverse chloride shift happen
at pulmonary capillaries
111
brief overveiw of chloride shift and reverse
chloride shift
- at systemic capillaries
- CO2 enters cell from tissues
- CO2 converted to HCO3 in RBCs
- Cl then moves into RBCs to restore homeostasis
reverse chloride shift
- at pulmonary capillaries
- HCO3 converted to CO2 in RBCS
- CO2 leaves cell to alveoli
- Cl leaves the cell to restore homeostasis
112
two main centres of breathing
medulla oblongata
pons
113
medullary respiratory group
divided into dorsal and ventral respiratory groups
dorsal - quiet normal exhalation/inhalation
ventral - forceful inhalation/exhalation
114
dorsal respiratory group
controls normal quiet breathing
part of the medullary respiratory group
115
ventral respiratory group
part of the medullary group
controlled by dorsal group
- work with Dorsal for inhalation
- control exhalation
- only forceful breathing
116
pontine respiratory group
affect normal breathing by influencing the DRG in the medullary group
117
what permits us to control breath?
teh cerebral cortex
118
why cant we hold our breath for too long?
increased Pco2 and H+ in blood stimulate DRG neurons which force normal breathing to resume
119
how do chemoreceptors influence breathing
sense changes in blood chemicals
(Pco2 and H+)
central - near medulla oblongata
peripheral - in aortic/carotid walls
120
hyperventilation is a response to:
low blood pH
- when pH is low, Pco2 is likely high
- chemoreceptors signal DRG to breath more
121
hypocapnia
when Pco2 is low, chemoreceptors do not send signals to the DRG
- can cause fainting due to hypoxia
- can result from hyperventilation
122
inflation reflex
prevents overstretching of lung tissue
- baroreceptors sense stretching and signal the vagus nerve to relax the respiratory muscles
123
other things that affect breathing (5)
emotions - both
temperature - lower/stop
pain - both
irritation of airways - increase
increased BP - lower
124
pulmonary perfusion
the extent of blood flow to the lungs
125
COPD - name and what it does
chronic obstructive pulmonary disease
- increased # of goblet cells and mucus secretion
- excess mucus impairs cillary function
126
emphasyma
immune destruction of alveolar walls
- leads to decreased surface area and decreased O2 acquisition
