Respiratory system organs
Nose, pharynx, larynx, trachea, bronchi and smaller branches, lungs and alveoli
Where does gas exchange with blood occur?
What are the structures (everything besides the alveoli)?
Conducting passageways that purify, humidify, and warm incoming air
Only externally visible part of the respiratory system
Inside of the nose
Midline dividing the nasal cavity
Where does most of the cleansing, warming, and moistening of air occur?
In the nasal cavity, due to the mucus
What do the ciliated cells of the nasal mucosa do?
Create a current that sweeps the contaminated muscus to the throat (pharynx) where it is swallowed and digested in the stomach
Projections within the nasal cavity that increse the surface area of the mucosa exposed to the air and increase air turbulance in the nasal cavity, deflecting particles onto the sticky mucus
Partition separating the nasal and oral cavities
Anterior bone-supported part of the palate
Unsupported posterior part of the palate
Failure of the bones forming the palate to fuse medially, results in breathing difficulty as well as problems with speaking and chewing, but can now be fixed easily
Located in the frontal, sphenoid, ethmoid, and maxillary bones, these lighten the skull and give voice resonance; they also produce mucus, which drains to the nasal cavity
Inflammation of the nasal mucosa caused by cold viruses and various allergens; excessive mucus is produced causing nasal congestion and postnasal drip
Sinus inflammation that is difficult to treat and causes voice-quality to change
Caused when passageways connecting the sinuses to the nasal cavity are blocked with mucus or infectious matter, this occurs when the air in the sinus cavities is absorbed, resulting in a partial vacuum
Muscular passageway about 5 inches (13 cm) long that resembles a short length of red garden hose; the throat, which serves as a common passageway for food and air
Posterior nasal aperture
Joining point of the pharynx and nasal cavity
Upper region of the pharynx, where air enters fro mthe nasal cavity
Mid region of the pharynx
Lower layer of the pharynx, just before the larynx and esophagus, for air and food (respectively)
Which is in anterior, the larynx or esophagus?
Eustachian canal opens into the...
Adenoid, located high in the nasopharynx
In the oropharynx at the end of the soft palage
Lie at the base of the tongue
Phayngeal tonsil becomes inflamed, obstructing the nasopharynx and forcing the patient to breathe through the mouth, so air is not moistened, warmed, or filtered...
Voice box; routes air and food into the proper channels and plays a role in speech; inferior to the pharynx, it is formed by eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage
Spoon-shaped flap of elastic cartilagethat protects the superior opening of the larynx; when we are not swallowing, it doesn't restrict air flow, but when we swallow, the larynx is pulled upward and the epiglottis tips, forming a lid over the opening to the respiratory system
Occurs when anything other than air enters the larynx, this expels the substance and prevents it from going down to the lungs
Larges of the cartilage rings; thyroid cartilage; shield shaped
Vocal folds (true vocal cords)
Vibrate with expelled air, allowing us to speak
Slitlike passageway between the vocal folds
Windpipe; 4 inches; passageway inferior to the larynx that is rigid because of the C-shaped rings of hyaline cartilage, which serve to support the walls of this tube (keep it open during breathing, despite pressure changes), and also to allow the esophagus to expand anteriorly when we swallow
Forcing air out of someone's lungs to expel obstrucing food
Performed in some emergency cases of obstructed breathing, tubes are placed in the trachea to allow air to enter; lots of much is formed...
Cilia in trachea
Beat continuously to propel mucus (w/ dust and debris) away from the lungs to the throat, where it is swallowed or spat out
Smoking inhibits ciliary activity, so smokers should avoid medications that...
Inhibit the cough reflex, as without their cilia, coughing is the only way the dirty mucus is kept out of the lungs
Right and left main (primary) bronchi
Fomed by the division of the trachia
Wider, shorter, straighter bronchi
More common bronchi for objects to become lodged in
Large organs occupying the entire thoracic cavity except the mediastinum
Most central part of the thoracic cavity, which houses the heart, great blood bessels, bronchi, esophagus, and other organs
Superior portion of each lung
Broad lung area resting on the diaphragm
How many lobes does the left lung have?
How many lobes does the right lung have?
Serosa lining the lungs
Serosa lining the thoracic cavity
Potential space between the layers of serosa
Breathing needs adhesion...
Inflammation of the pleura, which can be caused by decreased secretion of pleural fluid, causing pleural surfaces to become dry and rough, resulting in friction and stabbing pain with each breath; OR excessive amounts of fluid may be produced, putting pressure on the lungs and hindering breathing, which is painful, but not as bad as the first type
Smallest conducting passageways
Terminal bronchioles lead to...
Respiratory zone structures, which terminate in alveoli
Air sacs where gas exchange occurs
Lung tissue balance
Stroma (mainly connective tissue that allows the lungs to recoil passively when we exhale)
The lungs weigh about...
2 1/2 pounds
Walls of alveoli composed of...
A single, thin layer of squamous epithelial cells
Connect neighboring air sacs, providing alternate routes for air to reach alveoli whose feeder bronchioles have been clogged with mucus or otherwise blocked
Respiratory membrane (air-blood barrier)
Alveolar and capillary walls, fused basement membranes, and occasional elastic fibers; gas flows on one side, blood on the other, and O2 and CO2 exchange by the simple laws of diffusion
Dust cells that wander around the alveoli picking up bacteria, carbon, and other debres
Scattered amid the epithelial cells, these secrete surfactant
Major function of the respiratory system
Provide the body with O2 and dispose of CO2
1. Pulmonary ventilation
2. External respiration
3. Respiratory gas transport
4. Internal respiration
1. Pulmonary ventilation
Air moves into and out of the lungs so gases in the alveoli are continually refreshed; breathing
2. External respiration
Gas exchange between pulmonary blood and alveoli (blood and body exterior)
3. Respiratory gas transport
O2 and CO2 must be transported between the lungs and body cells via the bloodstream
4. Internal respiration
At systemic capillaries, gas exchange between blood and tissue cells (blood and cells inside the body)
Use of O2, production of CO2...
Breathing depends on...
Volume changes occuring in the thoracic cavity (volume changes lead to pressure changes lead to flow of gases to equalize pressure)
Diapghragm and external intercostals _______ when you inspire, _______ the size of the thoracic cavity
Why do the lungs adhere to the thoracic walls?
Surface tension of the fluid between the pleural membranes
Volume within the lungs
Expiration is active or passive?
Narrowing of respiratory passages by spasms of the bronchioles, making it harder to exhale
Always negative, this is the normal pressure within the lungs, which prevents the collapse of lungs (a collapsed lung occurs if this pressure becomes equal to the atmospheric pressure)
Lung collapse rendering the lung useless for ventilation, occurs when air enters the pleural space through a chest would, or the visceral pleura ruptures
Presence of air in the intrapleural space, disrupting the fluid bond between the pleurae, this is reversed by drawing air out of the intrapleural space with chest tubes, allowing the lung to reinflate and resume normal function
Nonrespiratory air movements
Reflexive movements of air that may sometimes be produced voluntarily; the most common ones are coughing, sneezing, laughing, crying hiccuping, and yawning
Deep breath, closes glottis, air forced superiorly from lungs against glottis, glottis opens suddenly air blasts up, clears lower respiratory passages
Cough through the nove, depressin the uvula and cutting the oral cavity off from the pharynx, clears upper respiratory passages
Inspriation then release in short expirations, emotionally enduced
Crying but a bit different...
Diaphragm spasms initiated by irritation of diaphragm or phrenic nerves, sound made by air hitting the vocal folds of the closed glottis
Deep inspiration taken with open jaws, ventilates all alveoli
Factors affecting respiratory capacity
Size, sex, age, physical condition
Normal, quiet breating moves ___ mL of air
Tidal volume (TV)
Volume of air moved with each normal breath
Inspiratory reserve volume (IRV)
Amount of air that can be taken in forcibly over TV (2100-3200 mL)
Expiratory reserve volume (ERV)
Amount of air that can be forcibly exhaled after tidal expiration (1200 mL)
Air remaining in the lungs after all that can be exhaled is exhaled, allows gas exchange to keep going and keeps the alveoli inflated (1200 mL)
Vital capacity (VC)
TV + IRV + ERV = total amount of exchangeable air (4800 mL)
Dead space volume
Air that enters the respiratory tract but remains in the conducting zone passageways and never reaches the alveoli (150 mL)
Air that reaches the alveoli (350 mL)
Measurer of respiratory capacities
Made by air going through the trachea and bronchi
Vesicular breathing sounds
Made as air fills the alveoli (soft muffled breeze noise)
Crackle or wheezing sounds when breathing can be caused by...
Diseased respiratory tissue, mucus, or pus
O2 attaches to the hemoglobinin RBCs, forming
CO2 transports in plasma as
bicarbonate ions (HCO3-) (some also binds to hemoglobin, at its own binding site)
CO2 and H2O form...
Carbonic acid is unstable, and becomes...
H+ and HCO3-, which is good for regulating blood pH
Inadequate O2 delivery to body tissues (impaired O2 transport)
Blue skin means low O2
Unique type of hypoxia, as this molecule (odorless, colorless gas) competes vigorously w/ O2 for the same binding sites on hemoglobin, and actually has a higher affinity, so it wins... leading cause of death from fire, called the "silent killer," victims become confused and have throbbing headaches, skin becomes cherry red in rare cases, often being interpreted as a healthy blush; people who have this are given pure O2 until the bad molecules are cleared away
Where each gas goes during ext. resp.
O2 goes from alveoli to blood; CO2 goes from blood to alveoli
Where each gas goes during int. resp.
O2 goes from blood to tissues; CO2 goes from tissues to blood
Enzyme that speeds the conversion of much of the CO2 into bicarbonate ions
Diaphragm and intercostals
Nerves regulating breathing
Phrenic and intercostal nerves
Where are the neural centers that control breathing located?
Medulla and pons
Self-exciting inspiratory center
Contained in the medulla, this sets the basic rhythm of breathing; a pacemaker
In the medulla; inhibits the pacemaker in a rhythmic way
Normal breathing rate
12-15 respirations per minute
Normal respiratory rate
Where are the stretch receptors?
Bronchiles and alveoli
What do the stretch receptors do?
Respond to extreme overinflation, which may damage the lungs, by generating protective reflexes that begin expiration
More vigorous breathing, this occurs after strenuous exercising, but doesn't always involve much of a pace change; expiration becomes active, involving the abdomanal muscles and others to lift the ribs
If the ______ centers are suppressed, as with overdoes of ____________, ______, or _____, respiration stops and _______ occurs
medullary; sleeping pills; morphine; alcohol; death
Physical factors that affect basic breathing rhythm
Talking, coughing, exercising
Concious control of breathing, such as during singing and swallowing, swimming, or other activities; can only occur for a certain amount of time, and can be overridden when O2 supply is too low, or blood pH falls too much; this is why parents shouldn't be worried when toddlers try to hold their breath "to death"
Horror movie, bated (held) breath; scared, panting; cold and clammy touch, gasp; reflexes from emotional stimuli acting through centers in the hypothalamus
O2 and CO2 (mainly CO2) levels
Also, pH is quite important (and the same as CO2, as it becomes carbonic acid, decreasing pH)
How do changes in CO2, causing lower pH, get noticed?
CSF pH is influenced, which acts on the medulla
How do changes in O2 get noticed?
Peripheral chemoreceptors in the aorta and in the fork of the common carotid artery, which send impulses to the medulla when levels drop
Most important stimulus for breathing
Need to get rid of CO2
When does dropping O2 become the stimulus?
In people who retain CO2, such as those with emphysema, chronic bronchitis, or other diseases
Rapid, deep breathing, which blows of CO2 and decreases carbonic acid levels, returning pH back down to normal range
When blood becomes alkaline, or basic, breathing...
Slows and becomes more shallow, allowing CO2 to accumulate and bring pH up (hypoventilation)
Often results from increased carbonic acid levels caused by excessive hypoventilation
Often results from decreased carbonic acid levels caused by excessive hyperventilation
Blue skin due to low O2 levels
Breathing into a paper bag helps people who are _____ventilating
COPD stands for
Chronic Obstructive Pulmonary Disease
Chronic bronchitis and emphysema
COPD diseases have these things in common
(1) Smoking history, (2) Dyspnea increases in severity, (3) Coughing and pulmonary infections are common, and (4) most are hypoxic, and have acidosis which leads to respiratory failure
Labored breathing, or "air hunger"
Mucosa of lower respiratory passages becomes severely inflamed and produces excessive amounts of mucus, which impairs ventilation and gas exchange and dramatically increases the risk of lung infections, including pneumonias; "blue bloaters" due to hypoxia and CO2 retention, which occur early in the disease
Alveoli enlarge as the walls of adjacent chambers break through, and chronic inflammation promotes fibrosis, so as the lungs become less elastic, airways collapse during expiration, obstruction air outflow, and requiring energy for exhalation, exhausting patients; "pink puffers" as cyanosis doesn't appear until late in the disease; overinflation leads to barrel chest
Fatty molecule made by cuboidal cells, that lowers surface tension of the film lining the alveoli so they don't collapse when we breathe; not present until late in pregnancy
Infant respiratory distress syndrome (IRDS)
Surfactant is inadequate because infant is born early or mother is diabetic (or something else), causing dyspnea within a few hours of birth; they used to die but now pressure can be applied within the sacs so they don't collapse
Cystic fibrosis (CF)
Most common lethal genetic disease, this causes oversecretion of a thick mucus that clogs respiratory passages and puts the child at risk for fatal infections; impairs food digestion by clogging pancreatic ducts; makes sweat salty; caused by gene producing the CFTR protein which controls Cl- flow in and out of cells; people with this disease has CFTRs that get stuck in the ER, thickening mucus; therapy for the disease includes mucus-dissolving drugs and "clapping" on the chest, as well as antibiotics
Respiratory rate in newborns
5 yr old Rrate
Old age, Rrate _______
Sudden infant death syndrome (SIDS)
Healthy infants stop breathing and die in their sleep, sometimes getting the parents in trouble; sometimes due to neural problems or viral infections, but more than a third of the cases seem to be due to heart rhythm abnormality partially due to genetics
Chronically inflamed, hypersensitive bronchial passages, that respond to many irritants with dyspnea, coughing, and wheezing
TB and pneumonia
Used to kill lots, but antibiotics have decreased the threat
AIDS patients often have drug-resistant ________ now
Chest wall become rigid, lungs lose elasticity, vital capacity decreases, blood O2 decreases, sensitivity to CO2 decreases
Old people becoming hypoxic during sleep
Othe effects of aging (productive)
Ciliary activity decreases, phagocytes become sluggish; older people are more at risk for respiratory tract infections such as pneumonia and influenza