A&P 400 (respiratory system) Flashcards
repsiratory system
All of the structures involved in breathing (pulmonary ventilation) and external respiration
ppulmonary ventilationdefine
Pulmonary ventilation: airflow to/from the lungs
external respiration define
External respiration: gas exchange between the lungs and pulmonary circulation
respiration also inveolves
Respiration also involves internal respiration
internal respriation deinfe
gas exchange between systemic circulation and the tissues
respiraiton overview
…
homeostasis requires
a steady supply of O2
and constant elimination of CO2
Disruption?
= oxygen starvation & waste buildup
= rapid cell death
which 2 systems work together to make sure that our cells don’t die
respiratory system provides for gas exchange
cardiovascular system transports the respiratory gases
functions of repiratory system
1) external respiration,
2) ventilation,
3) protection (of air),
4) sound prodution,
5)smell/olfactory
extensive SA for gas exchange
move air from exchange surface of lungs along respiratory passageways
protecting respiratory surfaces from dehydration, temperature change, invasion of pathogens
produce sounds for speaking, singing, and other forms of communication
detecting odors via olfactory receptors in the superior portion of the nasal cavity
respiratory tract consists of
Nose
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Alveoli
what is the respiratory tract
branching passageway that carries air to/from gas exchange surfaces of the lungs
2 divisions of respiratory tract
Conducting portion
Respiratory portion
conducting portion of respiratory tract
(functional division)
Nasal cavity to larger bronchioles
No gas exchange
respiratory portion
(respiratory portion)
Smallest bronchioles (respiratory bronchioles) to alveoli
Where gas exchange occurs
what is another way the respiratory tract can be categorized / termed?
Can also divide into the upper respiratory tract and lower respiratory tract
functionally terming —>
nose, pharynx, larynx, trachea, bronchi, bronchioles
======>conducting portion
WHEREAS
bronchioles –> alveoli
====== RESPIRATORY PORITON
whereas for lower/uppre rt —>
nose/pharynx - Upper RT
larynx, trachea, bronchi, bronchioles, alveoli,
==== LOWER RT
What are anaotmical structures OF UPPER RT
Nose
Nasal cavity
Paranasal sinuses
Pharynx
what are functions OF URT
Filters (e.g. hairs), warms, and humidifies incoming air
Protects delicate lower tract
Reabsorbs heat and water in outgoing air
LOWER RT –> structures
Larynx
Trachea
Bronchi
Bronchioles
Alveoli
functions of LRT
Conducts air to and from gas exchange surfaces
Respiratory epithelia
… varies depending on where in respiratory tract
1) Respiratory mucosa
Lines the nasal cavity and superior pharynx
Also lines the superior portion of the lower respiratory tract
—> larynx, trachea, bronchi, etc.
—> ciliated columnar with goblet cells (mucus secretion)
2) Stratified squamous epithelium
Lines inferior portions of pharynx
—> oropharnx and hypopharynx (laryngopharynx)
—> protect from abrasion during swallowing ingested food
WHY INFERIOR PORTION OF PHARYNX STRATIFIED SQUAMOUS????
B/c food passes here briefly
3) Simple cuboidal or simple columnar
Lines the smaller bronchioles
note ciliated cells?
trap pathogens, propel debris upward
what about where not ciliated?
macrophages
4) Simple squamous epithelium
Forms gas exchange surfaces
Distance between air and blood in capillaries is less than 1 µm
1) RESPIRATORY MUCOSA
whre?
what tpye of cells?
Respiratory mucosa lines nasal cavity through large bronchioles
Pseudostratified ciliated columnar epithelium with mucous cells
Lamina Propria
underlying areolar tissue
(LOOSE CT)
( underneath respiratory mucosa)
supports respiratory epithelium
mucous glands in trachea and bronchi
mucous cells (different from mucous glands?)
b/w the…
Pseudostratified ciliated columnar epithelium with mucous cells
THE MUCOCILIARY ESCALATOR
Flow of mucus/trapped debris (VIA CILIA)
Sticky mucus produced by mucous cell and MUCOUS GLANDS
Traps debris particles
Moved by beating cilia
where does mucociliary escalator sweep the mucous?
Swept toward pharynx
Swallowed (to acids in stomach) or coughed out
Epithelial stem cells replace damaged/old cells
Anatomy of URT
..
nose
Nose is primary route for air entering respiratory system
what is trhe visible portion of nose?
External nose is the portion you can see
what are external NARES
Nostrils or external nares
Paired openings into nasal cavity
what is the structure of the extenral nose
Bony and cartilaginous structures make up the framework of the external nose
bony framework of nose
Dorsum of nose
(bridge) formed by two nasal bones
Maxilla and frontal bones also contribute
Cartilaginous framework of the external nose
NASAL CARTILAGES:
small, elastic cartilages extending laterally from bridge; help keep nostrils open
I.e.
Septal cartilage
Lateral nasal cartilage
Alar cartilage
nasal cavity (BORDERS)
superior border
inferior border
medial border
lateral border
supeior border
Superior border: ethmoid bone
inferior borer
Inferior border: hard palate, made of palatine bones and palatine process of maxillae
medial border
Medial border: nasal septum
latearl border
Lateral border: ethmoid bone, maxillae, lacrimal bones, palatine bones, and inferior nasal conchae bones
The nasal cavity
…
majority of nasal cavity is
Majority lined with respiratory mucosa
what does the nasal cavity anteiroly merge with
anteriorly merges with the external nares
what does nasal cavity posteriorly communicate with?
posteriorly communicates with the NASOPHARYNX through the CHOANAE (AKA internal nares)
choanae etymology
The term is a latinization from the Greek χοάνη, “choanē” meaning funnel.
The choanae ( sg. : choana), posterior nasal apertures or internal nostrils are two openings found at the back of the nasal passage between the nasal cavity and the pharynx
SINGULAR CHOANA
NASAL VESTIBULE
nasal vestibule lined with course hairs for filtering large dust particles
” The area just inside the nostril (nose opening) that leads into the nasal cavity. The nasal vestibule is supported by the cartilage of the nose and is lined with tissue that contains short, coarse hairs.”
functional divison of nasal cavity
Respiratory Region
olfactory portion
Respiratory Region
Larger, inferior region of nasal cavity
Lined w non-keratinized pseudostratified ciliated columnar epithelium with many goblet cells (respiratory mucosa)
Olfactory Region
Smaller, superior region of nasal cavity
Olfactory receptors near superior nasal concha
Have cilia, but no goblet cells
what is respiratory region of nasal cavity lined with (WHAT CELL TYPE???)
NON_KERATINIZED pseudostratified ciliated columnar epithelium
(WITH MANY GOBLET CELLS)
—> I.e.
respiratory mucosa
structure sof nasal cavity
Nasal septum:
Divides right and left nasal cavities
nasal septum formed by
Septal cartilage
Vomer
Perpendicular plate of the ethmoid
structures of the nasal cavity (continued)
conchae and meatuses
Superior, middle, and inferior nasal conchae (bones)
Superior, middle, and inferior nasal meatuses
what is the purpose of meatuses
Passages between nasal conchae
Swirl incoming air to trap small particles
Moves odorants to olfactory receptors
Warms/humidifies air
WHAT ABOUT THE Paranasal sinuses
Frontal, ethmoid, maxillary, and sphenoidal sinuses
Open into nasal cavity
functions of paranasal sinuses
Mucus secreted by sinuses moisten nasal cavity
Resonate sound
Lighten skull
what are NASAL POLYPS (structures related to paranasal sinuses)
outgrowths of mucous membranes
usually found around openings to paranasal sinuses
(not necessarily normal? Can be symptomatic)
what are the NASOLACRIMAL DUCTS?
the LACRIMAL sac drains tears from the eyes
the nasolacrimal duct carries tears from thelacrimal sacof the eye into the nasal cavityNw
basal tears
Basal tears are in your eyes all the time to lubricate, nourish and protect your cornea. Basal tears act as a constant shield between the eye and the rest of the world, keeping dirt and debris away.
reflex tears
Reflex tears are formed when your eyes need to wash away harmful irritants, such as smoke, foreign bodies or onion fumes.
emotional tears
Emotional tears are produced in higher quantities than basal tears. They may be the same amount or more than reflex tears. Unlike, basal and reflex tears, emotional tears can be held back by the individual voluntarily, and they can stop when they want to.
three types of tears
We cry to protect our eyes, to wash out irritants and because, well, we are moved to tears.
“There are three types of tears:
basal tears,
emotional tears
and reflex tears,”
explains David Silverstone, M.D., a professor of ophthalmology at the Yale School of Medicine.
Epiphora
Epiphora is the medical definition for having excess tears or watery eyes.
It’s caused by your eyes producing too many tears, or the tears in your eyes not draining away as they should.
AND SO… what is the purpose of the NASOLACRIMAL DUCTS/system
The purpose of the nasolacrimal system is to drain tears from the ocular surface to the lacrimal sac and, ultimately, the nasal cavity.
what happens if the nasolacrimal ducts are not functioning properly
EPIPHORA
Blockage of the nasolacrimal system can cause tears to flow over the eyelid and down the cheek; this condition is epiphora.
Epiphora etymology
late 16th century (in epiphora (sense 2)): via Latin from Greek epi ‘upon’ + pherein ‘to bear or carry’.
And so… WHY DO YOU GET runny nose after crying (rhinorrhea?)
When you cry, tears come out of the tear glands under your eyelids and drain through the tear ducts that empty into your nose. Tears mix with mucus there and your nose runs.
I.e.
They go through the NasoLacrimal Ducts
why does lacrimation take place in response to emotions? (emotional tears)
your limbic system — the part of your brain that regulates emotions — sends a signal to your brain’s message system to activate your lacrimal glands to produce tears.
note about lamina propria
Lamina propria (basement membrane) of nasal cavity has extensive network of vessels
what functions take place in nasal cavity?
Release heat to warm inhaled air
Water from mucus evaporates to humidify inhaled air
as a result of heating mechanism in nasal cavity
Air moving from nasal cavity to lungs:
—-> Heated to almost body temperature
—-> Nearly saturated with water vapor
On the other hand…
during exhalation:
The reverse process occurs during exhalation
—> mucosa reabsorbs heat and water; reduces heat loss and water loss to environment
—> Releases air (with CO2) – taking as much heat/water from released air as possible
WHAT IS something that eliminates these benefits?
Mouth breathing eliminates these benefits
Let’s discuss the pharynx
…
what two systems is the pharynx a part of?
Pharynx is shared by respiratory and digestive systems
what is the colloquial term for the pharynx?
Colloquially referred to as the throat
describe the pharynx
5 inch muscular tube from CHOANA (internal nares?) to cricoid cartilage
what is the pharynx lined with?
Lined with respiratory mucosa
–> except oropharynx and hypopharynx (laryngopharynx) – lined w/ stratified squamous
what is the function of the pharynx?
passage for food and air
resonating chamber for speech
lymphatic tissue (tonsil) to prevent the entry to the body
—> entry?? pathogens? ?
tonsils
(NOTE MALT —> mucosa associated lymphatic tissue)
The tonsils are lymph nodes in the back of the mouth and top of the throat. They help to filter out bacteria and other germs to prevent infection in the body.
A bacterial or viral infection can cause tonsillitis.
Strep throat is a common cause.
three regions of pharynx
1) Nasopharynx
2) Oropharynx
3) Laryngopharynx
Nasopharynx
superior part of the pharynx
Lined with respiratory mucosa
possibly, the oropharynx is the region with
non-keratinized stratified squamous epithelium
yes
“The stratified squamous epithelium of the oropharynx is continuous with the laryngopharynx”
“Anteriorly, the laryngopharynx opens into the larynx; whereas, posteriorly, it enters the esophagus.”
boundaries of the nasopharynx
From choanae to soft palate
what is a unique struture contained by the NASOpharynx
Has pharyngeal openings of the auditory tubes (EUSTACHIAN tubes)
what is another unique structure contained by the nasopharynx
Contains adenoids (pharyngeal tonsils)
adenoid etymology
aden = gland
oid
adenoids define
Adenoids are a patch of tissue that is high up in the throat, just behind the nose.
They, along with the tonsils, are part of the lymphatic system.
The lymphatic system clears away infection and keeps body fluids in balance.
The adenoids and tonsils work by trapping germs coming in through the mouth and nose.
eustachian etmyology
The Eustachian tube is named after the Italian anatomist Bartolomeo Eustachio (also spelled Eustachi and known by the Latin name Bartholomaeus Eustachius) who lived circa 1510-1574.
function of eustachian tubes
The primary function of the Eustachian tube is to equalize air pressure between the atmosphere and the middle ear.
Yawning and swallowing cause contraction of the muscles connected to the Eustachian tube, enabling the tube to open to small amounts of air.
why does airpressure need to be equalized?
The equalizing of middle ear pressure is crucial to the proper workings of the eardrum.
With equalized air pressure, the eardrum can vibrate appropriately and transmit sound.
OROPHARYNX****
middle part of the pharynx behind oral cavity
Lined with non-keratinized stratified squamous epithelium
boundaries of oropharynx
From soft palate to base of the epiglottis
glottis vs epiglotttis
The glottis opens into the windpipe and is responsible for the production of sound.
While the epiglottis is a cartilaginous flap on top of the glottis that prevents the food from entering the larynx.
Laryngopharynx
inferior part of the pharynx
Lined with non-keratinized stratified squamous epithelium
(NOTED ABOVE)
laryngopharynx boundaries
From epiglottis to cricoid cartilage
Anatomy of LRT
…
LARYNX
Cartilaginous tube that surrounds/protects glottis (“voice box”)
Connects the pharynx with the trachea
—> Anterior to C4 – C6
note term
laryngeal skeleton
what are the three large cartilages that make up the larynx
1) Epiglottis
2) Thyroid Cartilage
3) Cricoid Cartilage
an important note
even though epiglottis and laryngopharynx are at the same level, they are different structures
epiglottis itself is part of larynx
however, the laryngopharynx is simply at the same level of the epiglottis
1) EPIGLOTTIS
projects superior to glottis, forms lid over it
During swallowing the larynx elevates, the epiglottis folds back over glottis, and blocks entry into respiratory tract
2) THYROID CARTILAGE
Prominent anterior surface is laryngeal prominence (Adam’s apple)
Thyrohyoid ligament attaches it to hyoid bone; other ligaments attach it to epiglottis and smaller cartilages (e.g. cricoid)
thyroid etymology
shield shaped
3) CRICOID ETYMOLOGY
Forms complete ring around larynx
With thyroid cartilage, protects glottis and larynx
provides attachment for laryngeal muscles/ligaments (muscles that control voice pitch, sound production, and so on)
cricoid etymoloy
ring-shaped
what is the landmark use for a treacheostomy?
Cricoid cartilage (directly above “)
what is a tracheostomy for?
A tracheostomy is a surgically created hole (stoma) in your windpipe (trachea) that provides an alternative airway for breathing
tracheotomy vs tracheostomy?
The term “tracheotomy” refers to the procedure to make an incision (cut) into the trachea (windpipe).
The temporary or permanent opening itself is called a “tracheostomy.”
However, the terms are sometimes used interchangeably.
why would a tracheotomy be necessary>
Medical conditions that make it necessary to use a breathing machine (ventilator) for an extended period, usually more than one or two weeks.
Medical conditions that block or narrow your airway, such as vocal cord paralysis or throat cancer.
Other catilage structures (three other minor cartilaginous structures of larynx)
Arytenoid cartilages (2)
Corniculate cartilages (2)
(elastic cartilage)
Cuneiform cartilages (2)
arytenoid catilages function
change position & tension of vocal cords via synovial joint w cricoid cartilage
cuneiform cartilages function
support vocal folds and lateral epiglottis
what is the glottis
where air passes through larynx
what does glottis consist of?
Made of VOCAL FOLDS
and RIMA GLOTTIDIS
(opening between folds)
glottis=
“the part of the larynx consisting of the vocal cords and the opening [Rima glottidis] between them. It affects voice modulation through expansion or contraction.”
rima define
a long narrow opening, esp between the vocal cords and the cartilages at the back of the larynx.
“Rima is Latin for a narrow cleft, crack or slit”
Vocal Folds
(Also known as the vocal cords)
VOCAL FOLDS = tissue folds that contain vocal ligaments
how are sound waves produced?
Vibration of VOCAL FOLDS produce sound waves
how are the vocal folds opened and closed?
Opened/closed by rotation of ARYTENOID cartilages
PHONATION define
Phonation = sound production from larynx
Vibration of vocal cords produces sound waves
ARTICULATION define
modification of sounds by tongue, teeth, and lips
where does amplification (part of articulation?) occur?
Amplification and resonance occur in pharynx, oral and nasal cavities, and paranasal sinuses
how do sound dynamics take place? and what role does larynx play in sound dynamics?
3 components:
producing sound
pitch
volume
1) Producing sound
bands of elastic ligaments stretched between laryngeal cartilages
muscles contract
= cartilages move
= pulls ligaments tight
= stretched vocal folds out into airway
= rima glottidis narrows
= air passes through folds and they vibrate
= sound
2) Pitch
Depends on tension of vocal folds
taut = rapid vibration = pitch
Androgens = thicker & longer vocal folds = lower pitch
3) Volume
Depends on the pressure of air
ventral, ventricular
late Middle English: from Latin ventriculus, diminutive of venter ‘belly’.
late Middle English: from Latin venter, ventr- ‘belly’ + -al.
ventricular folds of larynx
The ventricular folds, also known as the vestibular or false vocal folds are located above the true vocal folds and separated from them by the laryngeal ventricle
They are commonly referred as “false” vocal folds as they historically have been thought not to be directly involved in the production of “normal” voice.
ventricular folds funtion
aka false vocal cords
above true vocal cords
Space between = RIMA VESTIBULI
Useful for holding breath against thoracic cavity pressure
rima vestibuli vs rima glottidis
..
epithelium of larynx
depends on location:
1) superior to vocal fold
= non-keratinized stratified squamous epithelium (RECALL, UP TO CRICOID, LARYNGOPHARYNX IS STRATIFIED SQUAMOUS)
2) inferior to vocal fold
= pseudostratified ciliated columnar epithelium with goblet cells (respiratory mucosa)
THE PASSAGE OF AIR **
Trachea
—> Main Bronchi
—> Lobar Bronchi
—> Segmental Bronchi
—> Bronchioles
—> Terminal bronchioles to pulmonary lobules
passage of air via…
The trachea, bronchi, and bronchial branches convey air to and from lung gas exchange surfaces
trachea (windpipe) — at levels of…
Starts at C6 and ends at T5 by branching into bronchi
5 inches long
1 inch in diameter
esophagus vs trachea?
Lies in front of the esophagus
note the trachial cartilages
Has 15–20 C-shaped tracheal cartilages
what is function of tracheal cartilage?
Prevent collapse and overexpansion
allow esophagus to expand slightly into tracheal space
why does esophagus expand into trachea?
The hyaline cartilage in the tracheal wall provides support and keeps the trachea from collapsing.
The posterior soft tissue allows for expansion of the esophagus, which is immediately posterior to the trachea.
CARINA OF TRACHEA
ridge at the base of the trachea that separates the openings of the right and left main bronchi
carina define
a cartilage situated at the point where the trachea (windpipe) divides into the two bronchi.
etymology:
“keel”
note significant feature of structure/function of trachea (in the region of CARINA)
highly innervated mucosa
very sensitive cough reflex to prevent choking
—> prevent food/debris reaching bronchi
how are ends of c shaped tracheal catilages connected?
ELASTIC LIGAMENTS
as well as, TRACHEALIS (muscle)
what does contraction of trachealis do?
Contraction of trachealis narrows trachea; restricts airflow
why/when does tracheal diameter change?
Trachealis = how
why?
Tracheal diameter changes often, mostly controlled by sympathetic stimulation which increases airflow
note again tracheal cartilage shape/structure vs swallowing and esophagus
Tracheal cartilages are incomplete posteriorly allowing for expansion when swallowing
layers of mtrachea
mucosa
sub-mucosa
fibromuscular membrane
adventitia
1) mucosa (of trachea)
pseudostratified ciliated columnar epithelium with goblet cells (respiratory mucosa)
2) sub-mucosa (of trachea)
loose CT with seromucous glands
seromucous glands
release a mixture of mucus and antibacterial compounds. This mixture also serves to humidify and warm the air before it gets to the lungs.
3) fibromuscular membrane (with smooth muscle & elastic CT – INCLUDING TRACHEALIS mm)
(layers of trachea)
allow tracheal diameter change during inhalation/exhalation
4) adventitia (CT)
(layers of trachea)
binds trachea to other organs
Bronchi
..
main bronchi (s. bronchus)
aka primary bronchi
First division of bronchi
Right and left bronchus go into each lung
how do right and left main bronchi differ?
(Due to position of heart)
Right bronchus wider, at a steeper angle, and shorter than left
= foreign objects in trachea often go into it
why right/left bronchi different?
“The left lung has to accommodate the heart, which is positioned slightly towards the left side of the thoracic cavity. This anatomical arrangement causes the left bronchus to be more horizontal and curved to navigate around the heart.”
do bronchi have cartilaginous rings as well?
Have complete cartilaginous rings
note internal lining of bronchi
Lined with respiratory mucosa
Lobar Bronchi
(aka SECONDARY bronchi)
one lobar bronchi goes to each…
one goes to each lobe of the lung
(5 FIVE lobar bronchi)
—> 3 lobes on right
—> 2 lobes on left
(superior, middle, inferior lobes on right)
(superior, inferior lobes on left)
cartilage vs smooth muscle for lobar bronchi?
Smooth muscle encircles lumen and increasingly replaces cartilage
lobar bronchi internal lining
Also lined with respiratory mucosa
Segmental bronchi
(aka TERTIARY bronchi)
HOW MANY PER LUNG?
Each lung has approximately 10 segmental bronchi
what does each tertiary bronchus supply?
Each one supplies triangular shaped unit of lung
(BRONCHOPULMONARY segment)
bronchopulmonary segments
divisions of each LOBE
“A bronchopulmonary segment is a portion of lung supplied by a specific segmental bronchus and its vessels”
“These arteries branch from the pulmonary and bronchial arteries, and run together through the center of the segment.”
“Veins and lymphatic vessels drain along the edges of the segment.”
BRONCHIOLES
cartilage vs smooth muscle?
No cartilage; thick smooth muscle
what does HYALINE cartilage do for BRONCHI and TRACHEA
A layer of hyaline cartilage supporting the tracheal rings surrounds the submucosa.
The hyaline cartilage layer is sturdy but flexible and prevents the collapse of the trachea during expiration.
bronchioles – histology (LINED WITH…)
Ciliated simple columnar epithelium w goblet cells
& Ciliated simple cuboidal epithelium w/o goblet cells
(club cells or Clara cells)
recall:
simple cuboidal/columnar lines smaller bronchioles
Club cells (Clara cells)
Club cells, also known as bronchiolar exocrine cells,[1] are low columnar/cuboidal cells with short microvilli, found in the small airways (bronchioles) of the lungs.[2] They were formerly known as Clara cells.
broncholdilation
Sympathetic nervous system (NE/E) causes bronchodilation
—> increases airflow
bronchoconstriction
Parasympathetic nervous system causes bronchoconstriction
—> Decreases airflow
—> Histamine, asthma attack, allergies
extreme bronchoconstriciton
Extreme bronchoconstriction can occur during allergic reactions such as ASTHMA
lobes –> bronchopulmonary segments –> lobules
3 lobes (right lung)
+ 2 lobes (left lung)
= 5 lobes
right primary bronchus
= steep, wider, shorter
left primary bronchus
= angled, narrower, longer
(angled and longer to get around heart, narrower b/c less space)
In general, each lung has 10 segments
(TEN BRONCHOPULMONARY SEGMENTS)
Internally, each lobe further subdivides into hundreds of lobules.
bronchioles
—> TERMINAL BRONCHIOLES
—> Respiratory bronchioles
Bronchioles open into short segments called terminal bronchioles, which are thin-walled branches of the bronchioles.
Terminal bronchioles transition into respiratory bronchioles.
Respiratory bronchioles are lined by two types of epithelial cells:
(SAME AS bronchioles)
—> ciliated columnar cells and club cells (also known as Clara cells)
___NOTE THAT CLASS NOTES SAY THAT TERMINAL BRONCHI HAVE NON-CILIATED cells –> macrophage action instead
what do terminal—>respiratory bronchioles lead to?
Terminal bronchioles lead to PULMONARY LOBULES (for gas exchange)
i.e.
one main bronchus per lung
2 + 3 lobar bronchi per lobe
10 segmental bronchi (on each side) per BRONCHOPULMONARY segment
then many terminal/respiratory bronchioles PER lobule
terminal bronchioles
Many terminal bronchioles
Each terminal/respiratory bronchiole supplies a pulmonary lobule
Smooth muscle (no cartilage) = airway patency vulnerable to muscle spasms
terminal bronchioles –> LINING (histology
Non-ciliated simple columnar epithelium
macrophages remove debris (no cilia to move mucous)
respiratory bronchioles…
(according to class notes)
Many, many respiratory bronchioles
Simple cuboidal & simple squamous epithelium
—> AGAIN DIFFERENT FROM ABOVE
(follow classnotes)
respiratory bronchioles are…
First place where external respiration can occur, although limited
external vs internal repiration
Internal respiration occurs in the body tissues, where cells release carbon dioxide and take in oxygen from the blood.
External respiration occurs in the lungs or gills and occurs when the body takes in oxygen from the atmosphere and releases carbon dioxide.
review… (THE BRONCHIAL TREE)
Trachea: larynx to main bronchi in mediastinum
Main bronchi: one to each lung; cartilage rings are complete
Lobar bronchi: 3 in right lung, 2 in left; one per lobe
Segmental bronchi: branch to give rise to bronchioles
(one per bronchopulmonary segment)
Bronchioles
Terminal bronchioles
Respiratory bronchioles
review anatomy
Structural Division:
Upper Respiratory Tract
vs.
Lower Respiratory Tract
*
Functional Division:
Conducting Region
vs.
Respiratory Region
URT
nose, nasal cavity & pharynx
LRT
larynx, trachea, bronchi & lungs
Conducting region
nose, pharynx, larynx, trachea, bronchi, bronchioles, & terminal bronchioles
respiratory region (where gas exchange occurs)
respiratory bronchioles, alveolar ducts, alveolar sacs, & alveoli
gross anatomy of lungs
..
Each lung divided into lobes
Right lung (3): superior lobe, middle lobe, inferior lobe
Left lung (2): superior lobe and inferior lobe
(Each lobe has multiple bronchopulmonary segments)
—> 10 on right?
—> 9 on left?
right lung vs left lung
(SIZE)
Right lung is slightly shorter d/t liver
Left lung is 10% smaller d/t heart
how does lung form lobes?
DEEP FISSURES
Each lung is cone shaped and divided into lobes by deep fissures
right lung fissures
Right lung
horizontal fissure between superior/middle lobes;
oblique fissure between middle/inferior lobes
left lung fissures
oblique fissure between superior/inferior lobes
gross anatomy of lungs
(cone shaped)
Apex (tip) extends to superior border of first rib
Concave base rests on diaphragm
Cardiac notch—left lung; accommodates pericardium/heart
Root of lungs
dense connective tissue; fixes positions of bronchi, major nerves, blood vessels, and lymphatics
CONTAINS HILUM (?)
Hilum (of lungs)
medial depression on each lung
Allows passage of main bronchus, pulmonary vessels, nerves, lymphatics