week 2 Flashcards
(72 cards)
1
Q
define external respiration
A
movement of gases between the environment & body’s cells to supply O & remove CO2
2
Q
anatomy in the upper respiratory tract x4
A
- Mouth (oral) cavity (air & food)
- Nasal cavity (air only)
- Pharynx (air & food)
- Larynx (vocal cords, air only)
3
Q
anatomy in the lower respiratory tract x3
A
- trachea
- branching bronchi
- lungs
4
Q
functions of the nose x4
A
- warming of air before lungs
- filters air
- olfactory sense
- resonating chamber for speech
5
Q
functions of the pharynx x2
A
- passage for air & food intake
- equalise air pressure between the atmosphere & middle ear through the Eustachian tube
6
Q
function of the larynx x2
A
- contains the epiglottis = division of food
- contains the vocal cords (breath hold, vocalisation)
7
Q
function of false vocal cords, which are also known as _______
A
= vestibular folds
= close to block/hold breath e.g., when lifting a heavy object
8
Q
function of true vocal cords, which are also ______
A
= vocal folds
= elastic ligaments that when stretched, produce sound as air passes by them
9
Q
pitch define
A
degree of stretch
10
Q
amplitude
A
around of air pressure applied
11
Q
what are the 5 major functions of the respiratory system
A
(1) : conduction of air
(2) : conditioning of air and protection from inhaled substances
(3) : vocalisation
(4) : gas exchange
(5) : pH regulation
12
Q
if you half the radius of the tube then the resistance will increase by ____ times & based on what law
A
- 16 times
- Poiseuille’s law
13
Q
as resistance increases flow will ______
A
decrease
14
Q
how do you increase resistance & increase flow
A
increase diameter & increase length
15
Q
which has a higher SA the conducting system or the exchange surface ?
A
exchange surface
16
Q
what lines the conducting airways before it reaches the alveoli and for what reason
A
= respiratory mucosa & it conditions the air
17
Q
what temperature is air warmed to
A
37
18
Q
humidifying
A
water vapour is added till 100% humidity so exchange epithelium doesn’t dry
19
Q
roles of conduction of air x4
A
- respiratory mucosa
- warming
- humidifying
- filtering
20
Q
what structures are in the conducting system
A
- trachea
- primary bronchi
- smaller bronchi
21
Q
what structures are in the exchange surface
A
- bronchioles
2. alveoli
22
Q
functions of the mucosal lining
A
- traps & supports some pathogens
- ciliary beat = removes mucous & trapped pathogens
- relies on saline
23
Q
what is saline
A
= epithelial salt fluid
- secreted by epithelium cells of the respiratory system and works by increasing sodium in the airways which attracts water thus thinning out the mucous = easier to cough out
24
Q
what activates the secretion of saline
A
- Cl- secretion into the airway lumen from epithelial cells
- this draws Na+ into the lumen by electrochemical gradient
- H20 is drawn into the lumen by the concentration gradient
25
the mucosal lining is a fluid thus...
there is a surface tension drawing the wetted surfaces together especially in the elastic, flexible alveoli
26
define surface tension
property of the surface of liquid that allows it to resist an external force due to the cohesive nature of its molecules
e.g. placing a paper on a surface of water
27
Laplace law in relation to small & large alveoli & what is the bodies way of preventing the occurrence
the large alveoli receive more of the air because they have lower pressure and the small alveoli (higher internal pressure) receives little to none and this can cause collapse = atelectasis = no longer take part in gas exchange = less oxygen intake
- surfactant
28
what does Laplace law explain
the larger the radius the less pressure needed
29
function of surfactant & define in alveoli
= reduces surface tension when added to a liquid
- amphiphilic
- pulmonary surfactant coats the inside of the alveoli reducing surface tension = when air enters the alveoli both are inflated and the pressure is equalised = even distribution of ventilation = improvement in lung compliance
30
half life of surfactant
14 hours
31
when is surfactant formed
34 weeks into foetal life
32
what happens to premature births to do with breathing
surfactant hasn't been produced therefore, they experience respiratory distress requiring immediate therapy
33
how does surfactant work to equalise the pressure in a large and small alveoli
- it reduces surface tension more at lower pressure & less at higher pressure = giving alveolar stability & reducing the likelihood of alveolar collapse
34
define pH regulation
= when carbon dioxide is dissolved in blood (water)
increase CO2 = increase ph
35
define pH regulation
= when carbon dioxide is dissolved in blood (water)
increase CO2 = increase pH, therefore, altering ventilation = altering pH
36
the three processes required in vocalisation
1. Air must be in motion (muscles of respiration & clear airways)
2. Vibrations must be established in the air stream (vocal cords)
3. The bussing sound other vibrating air stream must be altered by the shape of the resonator (which includes the throat, as well as the oral & nasal cavities
37
what anatomy is involved in inspiration
- diaphragm which moves down toward the abdomen
| - external intercostals & scalene which pull the ribs up & out
38
what anatomy is involved in exhalation...does it actively use muscles?
= it is morally passive but may involve
- Internal intercostals antagonistic muscle group = return to relaxed position = passive
- Abdominal muscles which compress the abdominal cavity pushing viscera & the diaphragm upward
- Can be active because we can force air out so those muscles are also involved in inspiration but not as much energy in exhalation
39
describe the isolating action of the diaphragm (contract & relax)
contacts = flattens & decreases intrapleural pressure = increasing lung volume = assisting inspiration
relax = curves upwards, increasing intrapleural pressure = decreasing lung volume = assisting exhalation
40
define contract
decrease in size
41
explain Boyle's law
= pressure (P) of a mixed mass of material (e.g., air) is inversely proportional to volume (V)
- as pressure increases, volume decreases
42
how does Boyle's law relate to inspiration
- if we increase the volume in the lungs, the pressure will decreased
- means if we increase the volume of our lungs using muscles, the gas fills the lungs due to the pressure reduction as moves down the pressure gradient
43
how does Boyle's law relate to exhalation
- if we decrease the volume of the lungs, the pressure will increase within the lungs causing gases to move from the lungs to the atmosphere
- from high pressure to low pressure
44
if volume of fluid/gas increases, pressure _____
reduces
45
list the 5 steps one cycle of gas exchange
1. no air flow (alveolar pressure = atmosphere pressure)
2. air flows into the alveoli (inspiration muscles contract & increase thoracic volume = decreasing alveoli pressure = below atmosphere pressure
3. inward flow of air stops (when alveoli pressure = atmospheric pressure & lung volume is at its max)
4. air flows out of lungs (exhalation - inspiratory muscles relax & elastic recoil returns to diaphragm & ribs to their resting positions = thoracic volume increases = increasing pressure of alveoli above atmospheric pressure)
5. air movement stops (end of exhalation when PA is = to Patm again)
= one cycle
46
define intra-plural pressure
pressure of pleural fluid
47
how does lung tissue move, via muscle contractions?
- there is no muscle (non-contractile) thus it moves with the chest wall, due to cohesive forces generate by pleural fluid between membranes
48
expanding thoracic cage, causes ____ in intrapleural pressure which in turn causes the lung to _____ pressure & this is called____
1. decrease
2. decrease
3. inspiration
49
what is intrapleural pressure
pressure between lungs & thoracic wall
50
why is a negative intrapleural pressure important to alveoli
due to the alveoli been elastic, they naturally want to close, thus a neg intrapleural pressure is essential to keep them open & prevent them from collapsing
51
what happens if the intrapleural space is punctured
= air flows in = the intraplerual pressure (decreases) equalises to lung pressure (also atmospheric pressure) = the lack of neg intrapleural pressure on the elastic tissue of the lung means that the elastic tissue recoils to its unstretched state = collapses
52
what are the four pulmonary volumes & define each
1. tidal volume = amount of air inspired/expired in a single normal breath = 0.5Lish
2. inspiratory reserve volume = max amount of air that can be inspired above the normal tidal volume =3Lish
3. expiratory reserve volume = max amount of air that can be expired beyond the normal tidal volume = 1.1Lish
4. amount of air left in lungs after max breath out = 1.2Lish
53
define minute respiratory volume/minute ventilation (flow rate)
the rate at which air moves through the lungs
54
the tidal volume (Vt)
volume breathed with each breath
55
the respiratory rate (RR)
the number of breaths per minute
56
how to calculate the minute ventilation
Vt x RR
57
what are the four pulmonary lung capacities
1. vital capacity (all breath)
2. total lung capacity (all volumes)
3. inspiratory capacity (all breath in)
4. functional capacity (all exhalation & residual)
58
the higher the molecular weight the ______ the diffusion & solubility remains ______
1. slower
| 2. constant
59
the equation for the diffusion rate is
difference in partial pressures x cross sectional area of the pathway x solubility of the gas divided by the square root of the molecular weight of the gas x the distance of diffusion
60
lower partial pressure of oxygen in alveolus means
faster diffusion
61
more oxygen diffuses during ____
exercise
62
increase ventilation means increase ____ pressure in alveolar
carbon dioxide pressure in the alveoli = increase diffusion of carbon dioxide from the blood alveolus
63
define ventilation-perfusion ratio
increased ventilation increases partial pressure of alveolar oxygen, increasing diffusion of oxygen into & CO2 out of blood
64
perfusion
blood moving through capillaries
65
the more blood moving through capillaries the more ...
blood exposed to the surface
66
what is ventilation perfusion ratio equal to
alveolar ventilation divided by blood flow
67
what happens if the ratio is 0
= ventilation 0 = not breathing = blockage in airway
68
what if the ventilation perfusion ratio is moving towards infinite number
= little blood going through lungs = gases not moving in and out of blood stream = cells not able to survive = no circulation of blood = death
69
ideal ventilation perfusion ratio
1
70
low v-p means
= low ventilation or high perfusion
o Asthma
o Chronic bronchitis
o Acute pulmonary edema
71
high v-p
= High ventilation or low perfusion
- Pulmonary embolism (reducing lung blood perfusion)
- Emphysema (increased ventilation due to overwork to compensate for lung damage)
72
average cardiac output
5L per min
