Ch.13 : The Respiratory System Flashcards
1
Q
passageway through the respiratory system
A
nasal passage –. pharynx –> larynx –> tracheae (windpipe) –> bronchi —> bronchioles —> pulmonary alveoli
2
Q
diaphragm shaped
A
- dome shaped sheet of skeletal muscle
3
Q
the diaphragm seperates
A
the thoracic cavity from the abdominal cavity
4
Q
Plural sac
A
- double walled, closed sac
- seperates lungs from the thoracic cavity
5
Q
the pleural sac separates
A
the lungs from the thoracic cavity
6
Q
plural cavity location
A
- inferior to the pleural sac
7
Q
Intrapleural fluid is secreted by
A
the surface of the pleura
8
Q
intraplural fluid purpose
A
- lubricates pleural surface
9
Q
lungs location
A
- in the thoracic cavity
10
Q
the lungs contain
A
a large concentration of elastic tissue
11
Q
the lungs consist of
A
- highly branched airways, alveoli, and pulmonary blood vessels
12
Q
each lung is supplied by
A
one bronchi
13
Q
Alveoli purpose
A
- site of gas exchange
14
Q
what do alveolar wall consist of
A
type 1 alveoli cells
15
Q
purpose of type 2 alveoli. (3 things)
A
SECRETES SURFACNTANT
- decreases surface tension ; increases pulmonary compliance
- reduces lungs capacity to recoil (keeps them open—> prevents lungs from collapsing)
- maintains lungs stability
16
Q
Boyle / Mariottes Law definition
A
- at any temperature, the pressure excreted by the gas varies INVERSLEY with the volume of the lungs
17
Q
Changes in _____________ produce a flow of air in and out of the lungs
A
intra alveolar pressure
18
Q
What happens when the atmospheric pressure is lower than the intra-alveolar pressure?
A
air exists the lungs
19
Q
What happens when the intra-alveolar pressure is lower that the atmospheric pressure?
A
air enters the lungs
20
Q
Airflow goes from places of ______ pressure to areas of ______ pressure
A
- high
- low
21
Q
what is tidal volume?
A
- volume of air entering or leaving the lungs with a single breath
22
Q
average tidal volume
A
500ml
23
Q
What is the Inspiration Reserve volume (IRV)?
A
- extra volume of air that can be maximally inspired over and above typical resting tidal volume
24
Q
average IRV
A
3000 ml
25
What is expiatory reserve volume (ERV)?
- extra volume of air that can be actively expired by maximal contraction beyond the normal volume of air after a resting tidal volume
26
what is the average ERV
1000ml
27
what is the Residual Volume (RV)
- minimum volume of air remaining in the lungs after a maximal expiration
28
what is the average RV
- 1200 ml
29
what is Total Lung Capacity (TLC)
maximum volume of air that the lungs can hold
30
what is the average TLC
- 5,700 ml
31
TLC formula
TLC = VC + RV
32
What is vital capacity
- the max volume of air that can be moved in / out in a single breath following maximum inspiration
33
average VC
4500 ml
34
VC formula
VC = IRV + VT + ERV
35
what is pulmonary ventilation
- volume of air breathed in / out in one minute
36
Factors that change lung volume
- minute / pulmonary ventilation
- respiratory rate
37
pulmonary ventilation formula
TV x Resp. Rate
38
what is alveolar ventilation
- volume of air exchanged between atmosphere and the alveoli per minute
39
Alveolar ventilation formula
(TV - Dead space) x resp. rate
40
What is automatic dead space
- out of tatal inspired air at the site of gas exchange in the alveoli, a portion that remains in the conducting airways
- not avaiable for cellular respiration
41
Average amount of dead space
150ml
42
pressure consideration in ventalation consist of:
- atmospheric pressure
- intra-alveolar pressure
- intrapleural pressure
- transmural pressure
43
atmospheric pressure is also called
barometic pressure
44
intra -alveolar pressure is also called
intra pulmonary pressure
45
intrapleural presssure in as called
intra-thoracic pressure
46
average baromatic pressure
760 mm Hg
47
transmural pressure lacation
- within the walls of the lungs
48
muscle of quiet breathing (quite inspiration)
- diaphragm
- external intercostal muscles
49
Muscles of deep breathing (Inspiration)
- diaphragm
- external intercostal muscles
- accesory muscles of inspiration
50
Accessory muscles of inspiration consist of (2)
- sternocleidomastoid (SCM)
- scalenes
51
Muscles of expiration (forced breathing)
- internal intercostal muscles
- diaphragm
- abdominal muscles
52
Air flow formula
- F = R/P
53
p
(F=R/P)
the difference between atmospheric pressure and intra-alveolar pressure
54
R
(F= R/P)
- resistance of airways (radius)
55
resistance in a health persons lungs
radius remains large --> resistance remains low
56
Resistance in an astmatic person
radius can be small ---> resistance is high ----> less air moves into the lungs
57
Sympathetic nervous sytem occurs when
- stressed or exhasted
58
Sympathetic nervous system effect on the resistance
- secretes epinephrine ---> smooth muscle relaxation ---> bronchiodilation ---> decreased airway resistance
59
parasympathetic nervous system occurs when body is
- quite and relaxed
60
Parasympathetic nervous system effect on resistance
smooth muscle contraction ---> bronchioconstriction ----> increased airway resistance
61
Compliance
how much effort is required to stretch / distend the lungs
62
Purpose fo alveolar surface tension
- opposed the expansion of alveoli
- surface area of liquid tends to shrink because water molecules forcefully attach to each other (reduces surface tension)
63
accumulation of CO2 in the alveoli
- decreases airway resistance and increases airflow
64
increase in alveolar O2
brings about vasodilation
- increases blood flow to match larger airflow
65
blood is known as the "_______ transport system" between the lungs and the tissue
tranport system
66
Factors that affect the rate of gas transportation
- parietal pressure
- surface area
- thickness of the barrier
- diffusion coe-efficent for gas
67
as surface area increases the rate of gas transfer _______
increases
68
increase of the thickness of the barrier separating air and blood _______ the rate of gas transfer
decreases
69
rate of gas exchange is _______ proportional to the diffusion coefficent for a gas
directly
70
hwo to calculate parietal pressure
71
gases move _____ the parietal pressure gradient
down
(towards area of less concentration / pressure)
72
what percent of oxygen is transported in the plasma (physically dissolved)
1.5%
73
oxygen is _______ plasma soluble
poorly
74
what percent of oxygen is transported chemically bound to haemoglobin
98.5%
75
when oxygen is bound to hemoglobin it is called
oxyhemoglobin
76
What percent of carbon dioxide is physically dissloved
5-10%
77
what percent of carbon dioxide is bound to haemoglobin through transportation
5-10%
78
what percentage of carbon dioxide is transported as bicarbonate (HCO3)
80-90%
79
Medullary respiratory center (MO) contains
- Dorsal respiratory group (DRG)
- ventral respiratory Group (VRG)
80
DRG on effect
inspiration
81
DGR off effect
expiration
82
VRG only activates during
increased ventilation
EXAMPLE: excerisize, sex
83
Pneumotaxic center
- helps DRG to switch off the inspiratory neurons
84
Apneustic center
- prevents the inspiring neurons from being switched off
85
the apneustic center is found in the
pons
86
herring- breuer reflex is triggered
to prevent overinflation of the lugs
87
what are the chemical factors that play a role in determining the magnitude of ventlation
PO2
PCO2
H
