The respiratory system (Chapter 22) Flashcards
1
Q
- body tissues must be supplied with oxygen, CO2 waste must be disposed of
- CO2 can interfere with reactions
A
Gas exchange
2
Q
what are the four processes involved with gas exchange?
A
1. Pulmonary ventilation: breathing
2. External respiration: Gas exchange occurring in the lungs, O2 brought into lungs, CO2 brought out of the lungs
3. Transport of respiratory gases to/from tissues: not a function of lungs, function of cardiovascular system
4. Internal respiration: Gas exchange occurring in the tissues, deeper in body, remove oxygen from blood, pushes CO2 in blood to be transported for disposal
3
Q
what are the two zones of the respiratory system
A
Conducting zone and respiratory zone
4
Q
- respiratory passages leading from nose to the respiratory bronchiole
- transports air to/from the lungs
A
Conducting zone
5
Q
- actual site of gas exchange
- found in respiratory bronchioles, alveolar ducts and alveoli
A
respiratory zone
6
Q
- air is warmed and humidified as it passes thought this cavity (keeps a normal respiratory rate)
- cavity is so large it allows air to be warmed and humidifed before it reaches the lungs. Cold dry air causes a decrease in respiratory rate and slows down breathing
A
Nasal cavity
7
Q
What are the two cell types of nasal cavity (mucous membranes)?
A
- goblet cells- muscous producing cells
- seromucous nasal glands- “mucous” portion traps particles and debris, the “serous” portion secretes watery fluid containing lysozyme which destroy pathogens
- There are nerve endings in membrane- invading debris triggers a sneezing reflex (sneezing removes debris, removes air)
- Vascularization- capillaries and veins located superficially to help warm air as it passes through
8
Q
what 3 regions do the pharynx contain?
A
- nasopharynx
- oropharynx
- laryngopharynx
9
Q
- contains pharyngeal tonsils and tubal tonsils
- tonsils provide some immune defense
- closes during swallowing by soft palate and uvula (prevents u from getting food to nasopharynx)
A
Nasopharynx
10
Q
- meets oral cavity at isthmus of the facues
- contains palatine tonsils and lingual tonsils
A
oropharynx
11
Q
- where respiratory and digestive passage splits
- respiratory sits in front of digestive system
- split enters the lower conducting zone
A
laryngopharynx
12
Q
divides the laryngopharynx from the respiratory passages
A
lower conducting zone
13
Q
cartilage flap that closes off lower conducting zone
A
epiglottis
14
Q
- composed of thryoid cartilage and cricoid cartilage
- contains vocal cords for sound protection
- Glottis: open passageway surrounded by vocal cords
- vocal cords are ligaments composed of elastic fibers (fibers vibrate as we exhale to produce sound)
A
Larynx (voice box)
15
Q
A
16
Q
- if chords are tense=
- air passes across chords with greater force=
A
- if chords are tense= higher pitch
- air passes across chords with greater force= increase loudness
17
Q
composed of elastic fibers and cartilage rings
A
trachea (windpipe)
18
Q
smooth muscle tissue of trachea
A
trachealis
19
Q
allow air to reach the respiratory zone
A
bronchi
20
Q
bronchi bran 20-25 times, eventually form
A
bronchioles
21
Q
smallest of the bronchioles in conducting zone are
A
terminal bronchioles
22
Q
- organ where extenal gas exchange occurs
- composed of air space and elastic connective tissue
A
lungs
23
Q
point at which the bronchi and any blood/nerve supply enter/leave the lung
A
hilum
24
Q
pulmonary artery brings oxygen poor blood to lungs
A
Pulmonary circulation
25
immediately surrounds alveoli
pulmonary capillary network
26
bronchial arteries supply lung tissue with oxygenated systemic blood
bronchial circulation
27
nerve fibers enter lungs at
pulmonary plexus
28
parasympathetic causes the air tubes to become
narrow and constrict
29
sympathetic causes the air tubes to
dilate or become wider
30
thin, double layered serous membrane
Pleurae
31
covers thoracic wall and upper portion of diaphragm
parietal pleura
32
covers external lung feature
visceral pleura
33
fills cavity between visceral and parietal layers
pleural fluid
34
branch from the terminal bronchioles of the conducting zone
respiratory bronchioles
35
individual alveoli connected to "neighbors" via
alveolar pores
36
* squamous epithelial cells
* create walls of alveoli-where gas exchange occurs
Type 1 alveolar cells
37
* cuboidal cells scattered among Type 1 Cells
* secretes Surfactant-detergent like substance (every time you exchange air it leaves alveolar, if surfactant is not produced then the walls of alveolar will get stuck together and you can't unattached them
* secrete antimicrobial proteins-innate immunity
Type 2 alveolar cells
38
* Mobile cells
* consume debris, pathogens-protect internal alveolar surfaces
alveolar macrophage
39
the fow of air into and out of the lungs
Pulmonary ventilation
40
the exchange of respiratory gases across the alveolar wall
gas exchange
41
* the volume of a gas is inversely proportional to the pressure exerted by the gas on the walls of it container
* larger container=lower the pressure
* smaller container=higher pressure
* important for pulmonary ventilation
Boyle's Law
42
* pressure in the alveoli
* changes as you inhale or exhale
* but-always equalizes Patm at some point
Intrapulmonary pressure
43
* during contraction, diaphragm flattens
* During contraction, external intercostal muscles pull ribs up and outward
inspiration
44
* respiratory muscles relax and return to resting lenght
* Elastic fibers of lungs recoil-lungs become smaller in size
expiration
45
the amount of air that can be pushed into/out of lungs during ventilation
respiratory volume
46
* normal volume of air that moves into and out of lungs during normal breathing
* in healthy individuals- 500ml air
Tidal volume (TV)
47
# 1.
* amount of air that can be inspired forcibly past the tidal volume
* 2100-3000ml air
inspiratory reserve volume
48
* amount of air that can be forced from lungs after a normal tidal volume expiration
* 1000-1200ml air
Expiratory reserve volume (ERV)
49
* amount of air left in the lungs after forced expiration
* 1200ml air
* The lungs are NEVER empty of air
Residual (reserve) volume
50
the sum of two or more respiratory volumes
respiratory capacities
51
total amount of air that can be inspired after a normal tidal volume expiration
Inspiratory capacity (IC)
52
unable to expand, lungs cant expand to full extent so this usually results in a lost in elasticity in the lung tissue
Respiratory disorder
53
* healthy lung tissue is being destroyed somehow and being replaced with scar tissue
* scar tissue is not elastic
Pulmonary fibrosis
54
amount of air remaining in the lungs after a normal tidal volume expiration
Functional residual capacity
FRC= RV + ERV
55
total amount of exchangeable air
vital capacity
56
the total amount of air the lungs can hold after a maximum inhalation
total lung capacity
57
air that fills the conducting zone, but never contributes to gas exchange (nasal cavity, bronchi, trachea)
dead space
58
anatomical dead space for healthy individuals is ....
150ml air
59
* air reaches the alveoli, but no gas exchange occurs
* due to localized damage from mucus during illness, damage due to smoking
Alveolar dead space
60
anatomical dead space + alveolar dead space
total dead space
61
the total pressure exerted by a mixture of gases is the sum of the pressure exerted independenlty by each gas in the mixture
daltons law of partial pressure
62
p-atm of N2,02,C02,H20
p-alevoli of O2 and co2
P-atm+ 760mmHG
* 78.6% N2—597 mmHg
* 20.9% O2--- 159 mmHg
* 0.04%CO2--- 0.3 mmHg
* 0.46% H2O---- 3.7 mmHg
P-alveoli=760mmHg
* 13.7%O2--- 104 mmHg
* 5.2% CO2--- 40 mmHg
63
the pressure of each individual gas in the mixture is the....
partial pressure
64
* a gas will dissolve in a liquid in proportion to its partial pressure
* Gases dissolve in liquid best under high pressure, low temperature, and high solubility
Henry's law
65
gas exchange that occurs in the alveoli
external respiration
66
if pCO2 levels are low, bronchioles constrict
pCO2 ventilation
67
low pO2 - alveoli constrict
or
high pO2-alveoli dilate
pO2 perfusion (lungs)
68
how is oxygen transported?
* by Hb (4 O2 molecules per Hb molecules)
* binding first O2 molecule faciliatates bonding of other 3
* unloading first O2 molecule facilitates unloading of remaining 3
69
arterial blood is....saturated
venous blood is....saturated
98%, 75%
70
how is CO2 transported?
1. dissolved in plasma
2. bound to Hb (does not bind to heme, binds to amino acid of globulin)
3. as bicarbonate ions in plasma
71
* increase CO2 in blood, decrease pH
* slow,shallow breathing
respiratory acidosis
72
* decrease in CO2 in blood, increase pH
* rapid, deep breathing
respiratory alkalosis
73
central nervous system controls
medulla and pons
74
what are the two areas that set the normal respiratory rhythm
1. ventral respiratory group
2. dorsal respiratory group
75
Some neurons in this group fire during inspiration, others fire during expirationbut they cannot fire at the same time!!
Ventral respiratory group (VRG):
76
* modifies rhythm set by VRG
* Integrates information from other structures (chemoreceptors, etc.), delivers it to VRG
Dorsal respiratory group
77
* interacts with medullary respiratory centers to “smooth” the respiratory pattern
* Transition from inspiration to expiration (& vice versa)
* Found in pons
* balance inhalation and exhalation, prevents you from having a short inhalation and a long exhalation
* You bring in as much air as you breath out
Pontine respiratory center (PRC):
78
an increase in PCO2 levels in blood, pH decrease
hypercapnia
79
decrease in PCO2 levels in blood, increase pH
hypocapnia
80
* strong emotion & pain send information from hypothalamus & limbic system to respiratory centers
* Ex: excitation stimulates respiratory rate (happy and exciting =higher respiratory rate)
* Anger decreases it (not breathing enough)
* Ex: substantial drop in temperature can cause apnea
Hypothalamic control
81
* we can override the respiratory centers to control our own breathing depth/rate
* Cerebral motor cortex sends impulses to motor neurons that stimulate respiratory muscles
* This only goes so far (Ex: you cannot hold your breath forever)
cortical controls
82
ventilation increases 10-20x during exercise
hyperpnea
83
* Group of conditions characterized by a physiological inability to expel air from the lungs
* This condition is irreversible
* Features/shared characteristics: labored breathing, coughing, pulmonary infection, etc.
Chronic Obstructive Pulmonary Disease (COPD)
84
what are the 2 types of copd
1. Emphysema
2. chronic bronchitis
85
* permanent enlargement of the alveoli & eventual destruction of their walls
* Lungs lose elasticity
* Bronchioles collapse during expiration-trap air in alveoli
* Hyperinflation of alveoli leads to “barrel chest”
* Damage to alveoli results in damage to pulmonary capillaries
emphysema
86
* chronic production of excess mucous due to inhaled irritants
* Lower respiratory passages become inflamed over time & eventually fibrose
* Ventilation decreases
* This mucous is not removed from the lungs
* Bacteria & microorganisms thrive in stagnant mucousinfection is frequent
chronic bronchitis
87
* Some similarities to COPD, but is temporary bronchospasm attacks followed by symptom-free periods
* Bronchi become narrow and the individual has issues with breathing
* Allergic asthma is most common form-allergen causes inflammation of airways
* Inflammation caused by **IgE antibodies**
* **Inflammation persists between attacks-airways become hypersensitive**
* Treatment: inhaled corticosteroids (decrease inflammation and irritation) and/or bronchodilators (smooth muscle tissues in walls of bronchi to relax)
asthma
88
* Bacterial disease spread (primarily) by inhaled air
* Mostly affects lungs, but can spread to other organs
* 33% of world population is infected
* BUT, it’s not active in most
* **Immune response contains bacteria to hardened nodules in lungs-bacteria cannot cause infection**
* If active, symptoms include fever, night sweats, weight loss, racking cough, coughing up blood
tuberculosis
89
* Characterized by **temporary cessation** of breathing during sleep
* must wake up during sleep due to this condition
* Can be as high as ~30 times/hour
* Constant fatigue usually results-leads to increased susceptibility to hypertension, heart disease, stroke, etc.
sleep apnea
90
* occurs when upper airways collapse during sleep
* **Muscles associated with pharynx relax during sleep-airway sags and closes**
* Most common in men, made worse by obesity
* Treatment: CPAP machineblows air into passages constantly to prevent collapse
obstructive sleep apnea
91
respiratory centers of the brain “slack” during sleep-breathing rhythm/rate not maintained
central sleep apnea
