Respiratory Flashcards
Describe the major functions of the respiratory system. (3)
- Supply body with O2 for cellular respiration; dispose of CO2 (waste product of cellular respiration)
- olfaction
- speech
How does the respiratory system work with other organ systems?
Cardiovascular (2)
Lymphatic (3)
Nervous (1)
Endocrine (1)
Cardiovascular system
- blood is medium for gas transport
- blood pH buffered with bicarbonate ions
Immune system
- tonsils in pharynx house immune cells
- immune system protects respiratory organs from cancer, bacteria, etc
- help maintain blood volume
Nervous
-medullary and pontine centeres regulate respiratory rate and depth
Endocrine
-epinephrine dilates bronchioles
Describe the respiratory processes - ventilation, external respiration, transport, internal respiration, and cellular respiration. Which systems do they involve?
respiration is the movement of gas across the membrane
Describe and distinguish between the upper (4) and lower respiratory tracts (5).
upper = nose, nasal cavity, paranasal sinus, pharynx lower = larynx, trachea, bronchial tree, alveoli, lungs, pleurae
Describe and distinguish between the conducting and respiratory zones (3) of the respiratory tract. What does the conducting zone do?
Respiratory zone = site of gas exchange
-respiratory bronchioles, alveolar ducts, and alveoli
Conducting zone = conduits to gas exchange sites
- Includes all other respiratory structures
- cleanses, warms, humidifies air
What is inspiration vs expiration?
inspiration = gases flow into lungs Expiration = gases exit lungs
List, in order, the respiratory structures that air passes through during inspiration. (12)
nostril > nasal conchae > pharynx > larynx > trachea > primary bronchi > secondary bronchi > tertiary bronchi > terminal bronchioles > respiratory bronchiales > alveolar ducts > alveolar sacs
Anatomical features of the nasal cavity.
- What is the cavity superior to nostrils called?
- What is it lined with? (2)
- What opens into the nasopharynx?
- What consists of its roof? (2)
- What consists of its floor? (2)
- What 2 structures does it contain?
- nasal vestibule = cavity superior to nostrils
- lined with mucous membranes (olfactory & respiratory)
- divided by nasal septum
- Posterior nasal apertures (choanae) open into nasopharynx
- Roof-ethmoid and sphenoid bones
- Floor–hard (bone) and soft palates (muscle)
- nasal conchae & meatus
What does the olfactory and respiratory mucosa in the nasal cavity contain (3)? What is the functions of the respiratory mucosa?
-Olfactory mucosa contains olfactory epithelium
- Pseudostratified ciliated columnar epithelium, lysozyme and defensins
- Cilia move contaminated mucus down to the throat
What are the functions of the nasal cavity? (5)
Provides an airway for respiration Moistens and warms entering air Filters and cleans inspired air Serves as resonating chamber for speech Houses olfactory receptors
What are the Functions of the Nasal Mucosa and Conchae?
filter (inhalation), heat, and moisten air
Anatomical features of the paranasal sinus. (4)
What is its function? (3)
- In frontal, sphenoid, ethmoid, and maxillary bones
- Lighten skull;
secrete mucus; help to warm and moisten air
Anatomical features of the pharynx.
- what is it composed of?
- what are the 3 regions
Function
- Composed of skeletal muscle
- naso, oro, laryngopharynx
- Connects nasal cavity and mouth to larynx and esophagus
What is the nasopharynx? What is it lined with? What 3 structures does the nasopharynx contain?
Air passageway posterior to nasal cavity
Lining - pseudostratified columnar epithelium
Pharyngeal tonsil (adenoids)
opening of the Pharyngotympanic tube
tubal tonsil
What is the function of the oropharynx? What is it lined with? What 3 structures does it contain?
- Passageway for food and air from level of soft palate to epiglottis
- Lining of stratified squamous epithelium
- Isthmus of fauces, Palatine tonsils, Lingual tonsil
What is the laryngopharynx? What is it lined with?
- Passageway for food and air
- from epiglottis to larynx
- Lined with stratified squamous epithelium
Larynx attaches to ___ bone, open to ____ and continuous with ___.
What are its functions? (3)
-Attaches to hyoid bone; open into laryngopharynx; continuous with trachea
Provides patent airway
Routes air and food into proper channels
Voice production
Is epiglottis a cartilage? What is its function? What is it covered by?
yes - elastic cartilage
covers laryngeal inlet during swallowing; covered in taste bud-containing mucosa
What kind of cartilage makes up the larynx?
hyaline cartilage
What contains the vocal and vestibular folds? How is sound produced? Do vestibular folds parttake in sound production? What is its function?
- larynx
- vocal Folds vibrate to produce sound as air rushes up from lungs
- No part in sound production
- Help to close glottis during swallowing
Where is the trachea? What is it? What is its 3 layers? It contains what other 2 structures?
- Windpipe–from larynx into mediastinum
- mucose, submucosa, adventitia
- trachealis, carina
What is the function of the trachealis
Contracts during coughing to expel mucus
What is carina?
Point where trachea branches into two main bronchi
The bronchi makes up the ___. What is the order of structure? (7) How many lobar bronchi are there in each lung?
bronchial tree
-trachea > primary bronchi > hilum > secondary bronchi > tertiary bronchi > bronchials > terminal bronchioles
3 secondary bronchi on R, 2 on L
In the conducting zone, the amount of ___ increases to allow constriction.
smooth muscle
What does the respiratory membrane contain? What kind of cells make up each cell?
Alveolar walls made of type 1 alveolar cells (squamous epi)
type 2 alveolar cells (cuboidal) that secrete surfactants
Alvoli contain ___ cells to keep it sterile,
macrophages
What are the lungs composed of? What gives it elasticity? What is the hilum? Which lung is smaller and why? What separates the lobes?
- composed of alveoli
- stroma = elastic CT
- hilum = site for entry/exit of blood vessels, bronchi, lymphatic vessels, and nerves
- left smaller because of cardiac notch
In the pulmonary circulation, pulmonary arteries deliver ___ to ___ for ___. Pulmonary veins carry ___ from ___ to ___.
In the systemic circulation, bronchial arteries provide ___ to ___,
Pulmonary arteries deliver systemic venous blood to lungs for oxygenation
Pulmonary veins carry oxygenated blood from respiratory zones to heart
Bronchial arteries provide oxygenated blood to lung tissue
What is the order of pleurae? What is the function of the pleural fluid?
parietal > cavity > visceral
-Provides lubrication, assists in expansion and recoil
What cells/tissues make up the 3 layers of the trachea?
Mucosa-ciliated pseudostratified epithelium with goblet cells
Submucosa-connective tissue with seromucous glands
Adventitia-connective tissue; encases C-shaped rings of hyaline cartilage
How does the bronchi on the right side differ from the left? (3)
Right main bronchus wider, shorter, more vertical than left
Each lobar bronchus supplies ___.
Each lobar bronchus supplies one lobe
From bronchi to bronchiole, structural changes occur (3).
- elastic fibers replace cartilage
- amount of smooth muscle increases
- pseudostratified columnar to cuboidal epithelium
What makes up the respiratory membrane? (5)
alveolar & capillary walls, type 1 and 2 cells, basement membrane
Identify the muscles used during quiet inspiration, during forced inspiration, and during forced expiration, as well as the nerves responsible for stimulating those muscles.
quiet inspiration = external intercoastal & diaphragm
forced inspiration = muscles in neck
forced expiration = internal intercoastal, abdominal (oblique & transverse)
-all stimulated by the intercostal & phrenic nerve
Define and state relative values for atmospheric pressure, intrapulmonary pressure, intrapleural pressure, and transpulmonary pressure.
Patm = Pressure exerted by air surrounding body (1 atm)
Ppul = intrapulmonary pressure = Pressure in alveoli (Fluctuates with breathing, Always eventually equalizes with Patm)
Pip = intrapleural pressure = Pressure in pleural cavity (Fluctuates with breathing, Always a negative pressure < Patm or Ppul)
transpulmonary pressure - Ppul - Pip (4 atm), keeps airway open
Negative respiratory pressure is ___ than Patm.
Positive repiratory pressure is ___ than Patm.
Zero respiratory pressure = ___.
Negative respiratory pressure < Patm.
Positive repiratory pressure > Patm.
Zero respiratory pressure = Patm = 1
What happens when you get stabbed in the lung (break either visceral or parietal pleura? What is the condition called?
diaphragm drops, air rushes in and causes pneumothorax (air in pleural cavity) and intrapleural pressure becomes equal to intrapulmonary pressure. then the lungs cannot expand and collapse. transpulmonary pressure also increase,
Which pressure is affected in emphysema? Why do they have to breathe harder?
decrease in intrapulmonary (intra-alveolar) pressure (pressure in alveoli) because alveoli break down
-breathe harder because gas exchange is inefficient because alveoli SA decreases
What forces causes the lung to collapse? (2)
What are the forces that normally prevent lung collapse?
lungs tendency to recoil
surface tension of alveolar fluid (attract each other)
- reinforce negative intrapleural pressure
- elasticity of the walls
- the adhesive force between parietal and visceral pleura due to the pleural fluid
Where is resistance the greatest?
in the middle bronchiole (large airways compensate for friction & nonexistent at terminal bronchioles)
What are the steps of inspiration?
What are the steps to expiration?
What does epinephrine do to bronchioles?
dilate bronchioles and reduces air resistance (2 and tertiary)
What does surface tension do in ventilation?
reduces alveolar walls to smallest size (because liquid molecules attracted to one another)
What does the surfactant do in ventilation?
Reduces surface tension of alveolar fluid and discourages alveolar collapse
What is lung compliance? Higher the lung compliance, ___ to expand lung
Measure of change in lung volume (ability to distense or swell) that occurs with given change in transpulmonary pressure
-high = easier to expand
What decreases compliance (distensibility) of the thoracic wall? (3)
Deformities of thorax
Ossification of costal cartilage
Paralysis of intercostal muscles
What is lung compliance diminshed by? (3)
Nonelastic scar tissue replacing lung tissue (fibrosis)
Reduced production of surfactant
Decreased flexibility of thoracic cage
How do bronchiolar smooth muscle contractions affect ventilation?
constrict bronchioles to increase air resistance
What is the function of the thoracic cavity?
support and protect organs
What is
Tidal volume (TV) Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Inspiratory capacity (IC) Functional residual capacity (FRC) Vital capacity (VC) Total lung capacity (TLC)
IC = total amount of air that can be inspired after normal expiration FRC = vol of air remaining in the lungs after normal expiration TC = total amount of exchangeable air TLC = sum of all lung volumes
Respiratory capacity graph
What can spirometers distinguish between? What are each caused by?
obstructive pulmonary disease (increased airway resistance)
-increase in TLC, FRC, RV because lungs hyperinflate
restrictive disorders (reduced TLC due to disease/fibrosis) -decrease in VC, TLC, FRC, RV because lung expansion limited
What is an anatomical dead space? (2) Alveolar dead space? Total dead space? What does it contribute to?
anatomical dead space - No contribution to gas exchange/Air remaining in passageways
Alveolar dead space–non-functional alveoli
anatomical + alveolar dead space = total dead space
contributes to residual volume
If time
What is partial pressure? It is directly proportional to ___.
What are 3 factors that influence the dissolving of gas in a liquid?
Pressure exerted by each gas in mixture
Directly proportional to its percentage in mixture
Partial pressure
Solubility–CO2 > O2 >N2 dissolves in water
Temperature–as temperature rises, solubility decreases
What is external respiration? What promotes external respiration? (5)
- Exchange of O2 and CO2 across respiratory membrane
- increase in SA
- thinness of respiratory membrane promotes
- increase in steepness of partial pressure gradient (O2 has steeper gradient)
- increase in solubility (CO2 > O2 >N2 dissolves in water)
- decrease in mass (O2 moves faster because less weight than CO2)
What is perfusion and ventilation? How does ventilation-perfusion coupling work? What happens when ventilation is less than or greater than perfusion?
Perfusion-blood flow reaching alveoli
-arterioles dilate where O2 high to direct blood to high O2 site
Ventilation-amount of gas reaching alveoli
-bronchioles dilate where CO2 high to eliminate CO2 more rapidly
When ventilation < perfusion
- not as much air in the alveoli
- arteries contract to match the small amount of air
When ventilation > perfusion
- lots of air in the alveoli
- arteries dilate to make more blood go around alveoli
What is internal respiration? What causes O2 to flow from blood to tissues? For CO2 from tissues to blood?
- Capillary gas exchange in body tissues
- PO2 in tissue lower than in blood
- PCO2 greater in tissues
What is oxyhemoglobin? Reduced hemoglobin? Loading and unloading of O2 is facilitated by ___. As O2 ___ affinity for O2 increases; as O2 ___ affinity for O2 decreases. Fully saturated means ___ heme groups carry O2. Partially saturacted means ___ heme groups carry O2.
Oxyhemoglobin = hemoglobin-O2 combination
Reduced hemoglobin (deoxyhemoglobin) = hemoglobin that has released O2
shape of Hb
As O2 binds, Hb affinity for O2 increases
As O2 is released, Hb affinity for O2 decreases
Fully saturated (100%) if all four heme groups carry O2 Partially saturated when one to three hemes carry O2
What affects the Rate of loading and unloading of O2 (5)? What causes the oxygen-hemoglobin saturation curve to shift curve down and to the right? Up and to the left?
Po2 Temperature Blood pH (H+) Pco2 Concentration of BPG–produced by RBCs during glycolysis; levels rise when oxygen levels chronically low
down to the right
increase in PCO2, temp, H+, BPG lowers Hbs affinity for O2 (bohr effect), releasing it to the tissue
up and to the left with decrease in PCO2, H, temp, BPG
What is hypoxia?
Inadequate O2 delivery to tissues
What 3 forms are CO2 transported? In the order of amount used?
- vdissolved in plasma
- bound to globin of hemoglobin (carbaminohemoglobin)
- transported as bicarbonate ions (HCO3–) in plasma
State the reversible chemical equation for the reaction of carbon dioxide and water. Where does it primarily occur? Due to which enzyme?
Occurs primarily in RBCs, where carbonic anhydrase reversibly and rapidly catalyzes reaction
What is the chloride shift?
Outrush of HCO3- from RBC to plasma balanced by influx of Cl- from plasma to RBC
Predict how changing the partial pressure of carbon dioxide will affect the pH and the concentration of bicarbonate ions in the plasma.
Predict how changing the pH or the concentration of bicarbonate ions will affect the partial pressure of carbon dioxide in the plasma.
increase in PCO2 will decrease the pH and increase amount of bicarbonate ions in the plasma
increase in bicarbonate ions increase CO2 made which increases PCO2
State the reversible chemical equation for carbon dioxide binding to deoxyhemoglobin and predict how changing carbon dioxide concentrations will affect deoxyhemoglobin levels in the tissues and the lungs.
CO2 + Hb <-> HbCO2
CO2 dissociates from Hb in the lungs where PCO2 is lower than the blood
CO2 binds to Hb in tissues where PCO2 higher in the tissues than blood
more CO2 means more deoxyhemoglobin, more O2 means more oxyhemoglobin
What neurons control respiration?
-Neurons in reticular formation of medulla and pons
Ventral respiratory group
Dorsal respiratory group
What does the ventral respiratory group do? Which nerves does it involve?
- sets up eupnea - respiratory rhythm & rate
- excite phrenic (diaphragm) & intercoastal nerves (external intercostals)
What does the dorsal respiratory group do?
integrates neural input and sends info to the Ventral respiratory group
Where is the respiratory center located? What does it do? It fine-tunes breathing rhythms during ___ (3).
medulla and pons
modify activity of VRG (Smooth out transition between inspiration and expiration)
-fine-tune breathing rhythms during vocalization, sleep, exercise
Breathing depth is determined by ___.
Breathing rate is determined by ___.
- Depth determined by how actively respiratory center stimulates respiratory muscles
- Rate determined by how long inspiratory center active
Describe how changes in PCO2 and blood pH is regulated by the negative feedback mechanism.
What is hyperventilation/panting vs hypoventilation?
hyper - increased depth and rate of breathing (decrease blood CO2/hypocapnia)
hypo - decreased depth and rate breathing (increases blood CO2/hypercapnia)
What is eupnea, apnea (when does it occur), hyperpnea? How is hyperventilation different from hyperpnea?
eupnea - normal breathing
apnea - breathing cessation (may be due to abnormally low PCO2)
hyperpnea - increased ventilation due to metabolic need (like exercising)
difference - hyperpnea does not alter blood CO2 levels
***Analyze how oxygen and carbon dioxide movements are affected by high altitude
- at higher altitudes, hemoglobin and O2 affinity decrease because less O2 available and want O2 to be loaded onto the tissues
- BPG concentrations increase also decrease affinity to release more O2 to tissues
What factors influence external respiration?
- partial pressure gradients
- gas solubility
- thickness of SA of respiratory membrane
- ventilation-perfusion coupling
in voice production,
___ is determined by length & tension of vocal chords
___ is determined by force of air
pitch = is determined by length & tension of vocal chords loudness = is determined by force of air
What are the structures of a larynx?
-vestibular & vocal folds
