Anatomy of the Respiratory System

Question 1

What does the mesoderm and endoderm develop into for the pulmonary system?

Answer 1

mesoderm - smooth muscle around airways
endoderm - epithelial lining

Question 2

What does the pulmonary groove develop into? What does it grow out of?

Answer 2

becomes the trachea and eventually develops into the bronchi
grows out of pharyngeal pouches/area

Question 3

Why are the tubes and alveoli filled with liquid during embryonic development?

Answer 3

prevents development of soft tissue

Question 4

What are the anatomic separation of the respiratory tract? What structures are included?

Answer 4

ANATOMIC SEPARATION - upper and lower

UPPER: nasal cavity, pharynx, larynx

LOWER: trachea, primary bronchi, lungs

Question 5

What are the functional separations of the respiratory tract? What do they include?

Answer 5

FUNCTIONAL SEPARATION - conducting and respiratory zone

CONDUCTING ZONE: portions of airway where gases cannot diffuse; filters, cleanses, warms, humidifies air; rigid
- nasal cavity, pharynx, larynx, trachea, bronchi, bronchiole to terminal

RESPIRATORY ZONE: gas can diffuse, nonrigid, .REQUIRES SSET
- respiratory bronchiole, alveolar duct, alveolar sac

Question 6

What is the opening to the vestibule called? What kind of epithelium is it lined with? What ET lined the vestibule?

Answer 6

vestibule - space of the nostril
- opening: external nares - cornified SSET with hair

as vestibule completes, it loses hair and becomes non cornified SSET

Question 7

Where does the maxillary sinus drain?

Answer 7

drains higher into the middle meatus of the nasal cavity

Question 8

Describe the nasal mucosa.

Answer 8

contains large surface area
thin epithelium that is highly vascularized
incomplete basement membrane
direct absorption of drugs - bypasses digestive system

Question 9

Describe the epithelium of the nasal cavity. What kind of cells are unique to the two types of epithelium?

Answer 9

nasal cavity - lined with pseudo stratified columnar ET
- contains motile cilia to move mucous
- goblet cells - secrete mucous

olfactory epithelium - bipolar chemoreceptors
- olfactory nerve: CN1
- located in the roof of the nasal cavity
- neurons pass through the cribriform foramina

Question 10

Where does the nasopharynx start and stop? What kind of ET lines it? What opening does it contain? What tonsil?

Answer 10

starts: internal nares
stop: border of soft palate
ET: respiratory epithelium - pseudo stratified columnar
opening: internal auditory tube (inner ear)
tonsil: nasopharyngeal tonsil

Question 11

Where does the oropharynx start and stop? What kind of ET? What tonsil?

Answer 11

start: borer of soft palate
stop: epiglottis
ET: non cornified stratified squamous
tonsil: palatine and lingual (inferior)

Question 12

Where does the laryngopharynx start and stop? What kind of ET? What tonsil?

Answer 12

start: epiglottis of larynx
stop: opening of larynx - tip of arytenoid cartilage
ET: non cornified stratified squamous
tonsil: none

Question 13

What are the muscles of the pharynx? What innervates them? What are their origins and insertions?

Answer 13

constrictor muscles - innervated by vagus and some glossopharyngeal

superior constructor - originates at raphe
middle constructor - overlaps superior
- originates at hyoid
inferior constructor - overlaps middle
- originates at thyroid cartilage

ALL constrictor muscles insert at the median raphe of posterior pharyngeal wall

Question 14

What is the function of the larynx? Describe the following ligaments and membranes: thyrohyoid ligament, cricothyoid ligament, aryepiglottic fold

Answer 14

functions: provide airway, separate path or air from path of food, vocal production

thyrohyoid ligament: attaches thyroid cartilage to hyoid bone

cricothyroid ligament: attaches thyroid cartilage to cricoid cartilage

aryepiglottic fold - attaches arytenoid cartilage to epiglottis
- contains the corniculate and cuneiform cartilages

Question 15

What is the largest cartilage in the larynx and what does it form anteriorly? What is this and the other cartilage in the pharynx made of?

Answer 15

thyroid cartilage - completely open posteriorly
- anteriorly forms the laryngeal prominence (Adam’s apple) in males

made of hyaline cartilage

Question 16

Describe the cricothyroid muscle. What does it do? What is it’s antagonis? What is it innervated by?

Answer 16

Pulls thyroid cartilage anteriorly - attaches btw thyroid/cricoid cartilage

Lengthens vocal cord/increases tension - increases pitch

Antagonist - thyroarytenoid muscle

innervated by external laryngeal nerve - only one

Question 17

Describe the thyroaytenoid muscle. What does it do? What is its antagonist? What is it innervated by?

Answer 17

Pulls thyroid and arytenoid muscle together
Shortens vocal cords - decreases pitch
Antagonist - cricothyroid muscle
Innervated by recurrent laryngeal nerve (vagus)

Question 18

Describe the posterior cricoarytenoid muscle. What is its function? What is it innervated by?

Answer 18

abduction of vocal ligament - opens rima glottidis
- pulls on areytenoid and rotates them out

innervated y recurrent laryngeal nerve

Question 19

Describe the lateral cricoarytenoid muscle. What is its function? What is it innervated by?

Answer 19

adductor of the vocal cords - closes rima glottidis
brings vocal ligaments together

innervated by recurrent laryngeal nerve

Question 20

Describe the oblique and transverse arytenoid muscle. What are they innervated by?

Answer 20

adduction of vocal ligaments - closes rima glottidis
- both bring entire cartilage to the arytenoid together

transverse is deep to oblique

innervated by recurrent laryngeal branch

Question 21

Describe the vocalis muscle. What is it innervated by?

Answer 21

decreases tension of the vocal ligaments - decrease pitch
- some parts tense while others relax
- lies on top of and surrounds the vocal ligaments

innervated by the recurrent laryngeal nerve

Question 22

Describe the function of the following nerves: internal laryngeal branch, external laryngeal branch, recurrent laryngeal branch. What are they part of?

Answer 22

internal: sensory information only for larynx above true vocal cords

external: motor only - cricothyroid only - increase tension/pitch

recurrent: sensory from below vocal cords
- motor to ALL muscles besides cricothyroid
- loops around subclavian artery and arch or aorta back up

all part of vagus
- internal/external part of superior laryngeal nerve

Question 23

Describe the structure of the trachea. What kind of ET? What kind of cartilage? What is the muscle?

Answer 23

has lumen for air
ET - ciliated pseudo stratified columnar
Submucousa - seromucous glands
Cartilage - C shaped hyaline - gap posteriorly for swallowing
muscle - trachealis - smooth muscle - located at gap of cartilage

Question 24

Where is a tracheostomy usually located?

Answer 24

between the 3rd and 4th cartilage rings right at the thyroid gland
- thyroid is clamped in ER bc of vessels

Question 25

Which bronchi is larger? What is it separated by? If an object is inhaled, which side would it be likely found on?

Answer 25

right bronchus larger - larger radius, bigger lumen, more vertical
- more likely object will end up there

carina - piece of cartilage that separates the flow of air into R and L bronchus

Question 26

Describe the different bronchus branches. What kind of ET? what kind of cartilage? Muscle?

Answer 26

primary
- ET - ciliated pseudo stratified columnar
- continuous hyaline cartilage - C shaped ring
- cannot tell difference from trachea unless esophagus is seen
- circular ring of smooth muscle

secondary/tertiary
- ET - simple columnar to cuboidal with lots of cilia
- irregular plates of discontinuous hyaline cartilage
- circular ring of smooth muscle

Question 27

Describe the bronchiole. What kind of ET and cartilage and muscle?

Answer 27

most important airway for determining peripheral resistance to airflow
ET - simple cuboidal
NO CARTILAGE
continuous ring of smooth muscle - innervated to dilate by sympathetic

Question 28

What is the difference between terminal and respiratory bronchioles?

Answer 28

Terminal bronchiole - just proximal to appearance of respiratory bronchiole
- need to see respiratory bronchiole to identify terminal

Respiratory bronchiole - similar structure to bronchiole
- has individual air sacs blebbing from wall
- need to see alveolus before identifying respiratory
- still has simple cuboidal, but has outpouches of SSET alveoli

Question 29

Describe an alveolar duct. What kind of ET, cartilage and muscle?

Answer 29

As we move to the alveolar duct, we lost smooth muscle

alveolar duct - contains simple cuboidal and SSET
no cartilage
smooth muscle knobs at alveoli

Question 30

Describe the alveolus cells. What makes the respiratory membrane?

Answer 30

Type I alveolar cell - SSET
Type II alveolar cell - septal cell - coats the inside of cell with oily material that prevents walls of alveolus from sticking

alveolar macrophage - dust cells - migrate and picks up particulate matter, lots of lysosomes

respiratory membrane: formed between type I alveolar cell and SSET of capillary
- SSET sandwich with loose irregular CT in the middle

Question 31

Where are the lungs located? What is located in the pleural cavity?

Answer 31

located in the thoracic portion of the ventral cavity
surrounded by pleura, but on in pleural cavity

pleural cavity - contains pleural fluid ~ 2 tsp for lubrication for lung expansion - mostly inferior and posterior to lung
visceral - around lung - SSET with loose irregular CT
parietal - attached to surrounding chest wall and diaphragm

Question 32

Describe the regions and the surface of the lungs: apex, base, coastal surface, diaphragmatic surface, mediastinal surface

Answer 32

apex - top op lung - can be pulled into neck
base - also diaphragmatic surface - rarely touches diaphragm
costal surface - in contact with pleura covering ribs
mediastinal - where the heart goes

Question 33

Describe the fissures of the lungs. What’s the different between the R and the L?

Answer 33

R lung - 2 fissures, 3 lobes
superior lobe separated by horizontal fissure to middle lobe
middle lobe separated by oblique fissure for inferior lobe
- no middle lobe on posterior aspect

L lung - 1 fissure, 2 lobes
superior lobe - CONTAINS CARDIAC NOTCH and lingua
superior lobe separated by oblique fissure for inferior lobe

for both lungs:
- superior is anterior
- posterior is inferior

Question 34

Describe the hilus. What is another name for it? How can you tell L from R?

Answer 34

hilus - root of lung
- contains airways and blood vessels into/out of lung

R side - bronchus posterior to pulmonary artery
- contains impressions for azygous and superior vena cava

L side - bronchus inferior to pulmonary artery
- impression for the aorta

on both sides, the pulmonary veins are inferior to the pulmonary arteries