Resp. Anatomy Flashcards
What are the ideal conditions for gas exchange?
warm, clean, moist
What area of the body includes the upper resp tract?
chin up
What area of the body includes the LRT?
chin down
Define mucosa and what it is attached to
Mucosa = moist layer which lines most organs and is attached via basement membrane to lamina propria (CT, may contain glands)
how does the epithelium change along the length of the tract to reflect function?
Most of conducting region: respiratory epithelium
Where air & food travels: stratified squamous (for protection)
Site of gas exchange: simple squamous
Olfaction: olfactory mucosa
What is the long/proper name for resp epithelium?
pseudostratified ciliated columnar epithelium with goblet cells
Where is resp epithelia found?
nasal cavity, part of pharynx, trachea and bronchi
What is the function of goblet cells?
make + excrete mucus to trap debris and moisten air
What is the function of cilia?
move back and forth to push mucus (and .: bad stuff) towards pharynx to be swallowed
What structures make up the URT?
- Nose and nasal cavity
- Paranasal sinuses
- Pharynx
What are the functions of the URT? (4)
- Conducting passage (not just air)
- Prepares for resp membrane [warm, clean, moist]
Also:
- Paranasal sinuses: resonating chambers for speech
- Olfaction: sensory receptors
What is the function of the cartilages in the nose/nasal cavity?
Soft, flexible, maintain patent airway
What are 3 features of the vestibule?
- Lined with skin (for protection from nose pickers)
- Has sebaceous sweat glands, hair follicles [clean]
- Vibrissae (hairs) filter inhaled air
What bones make up the roof of the nasal cavity?
ethmoid and sphenoid bones
What bones make up the floor of the nasal cavity?
hard and soft palates
Describe the anatomy of the conchae
- On the lateral walls of the nasal cavity
- 3x projections of bones that curl around (superior, middle and inferior conchae)
- Covered in resp epithelium .: mucus
What is the function of the conchae?
Swirl air so that all air touches surface, mucus can pick up stuff and also can warm up = more time for warming + humidifying air, also olfaction detection
Where is the olfactory epithelium found? Function?
Found on roof of nasal cavity
- pick up chemicals that signal the brain => scent
How is air warmed in the nasal cavity?
Within the nasal mucosa, specifically within the lamina propria, we have a big, thin walled vascular plexus. This helps warm up incoming air (via radiation)
- When air temp drops, plexus dilates = greater heat transfer
- Close to the surface, easy to damage
○ This is generally where nose bleeds originate from
What are the functions of the paranasal sinuses? (3)
○ Lighten skull
○ Increased SA to clean, warm and moisten air
○ Sound resonance
Where do the sinuses drain into?
the pharnyx
What are the 3 regions of the pharynx? (order from top to bottom)
nasopharynx, oropharynx, laryngopharynx
What is the pharynx commonly known as?
the throat
T or F: food and air travels through the nasopharynx
F - air passage only
What type of mucosa is found in the nasopharynx?
respiratory mucosa
Where does the nasopharynx start and end?
internal nares to soft palate
What structures block the nasopharynx during swallowing to prevent food entering nasal cavity?
The soft palate and uvula (dangly thing)
What section of the pharynx do the auditory tubes drain into?
Nasopharynx
T or F: food and air travels through the oropharynx
True - air + food
What type of mucosa is found in the oropharynx? why?
Stratified squamous for protection against abrasion
Where does the oropharynx start and end? What structures does it include?
From soft palate to hyoid bone, incl. palatine and lingual tonsils
T or F: food and air travels through the laryngopharynx
True- air + food
What type of mucosa is found in the laryngopharynx? why?
Stratified squamous for protection against abrasion
Where does the laryngopharynx start and end?
From hyoid bone to opening of esophagus
- Ends where resp and digestive tracts diverge
what structures make up the LRT? (5)
- Larynx
- Trachea
- Bronchi
- Bronchioles
- Alveoli
What are the functions of the LRT? (3)
- Conducts air to/from site of gas exchange
- Completes warming/cleaning/moistening of the air
- Provides barrier between air and blood, large SA for gas exchange
Where is the larynx positioned?
- Ant. to esophagus
- Spans from hyoid bone to trachea
What are the 4 cartilage structures found in the larynx? What are their individual and collective functions?
○ Thyroid cartilage: grows during puberty in males b/c testosterone
○ Laryngeal prominence: protection
○ Cricoid cartilage: solid ring = keeps patent
○ Epiglottis: tongue pushes down => closes airway when swallowing
Collective function = to protect and maintain open airway
What is the glottis commonly known as?
voice box
What 2 folds are attached to the cartilages in the larynx?
The vocal and vestibular folds
Describe the vocal folds
- True vocal cords
- Passing air causes vibrations -> sound waves
- For normal voice
How does testosterone change the voice?
Testosterone affects cartilage and muscle
-> longer, thicker folds
-> deeper voice
Describe the vestibular folds
- ‘False’ vocal cords
- Superior to vocal folds
- Prevent foreign objects entering glottis
- Can produce very deep sounds (not normally used)
Where is the trachea found?
between larynx and primary bronchi
What are the functions of the trachea? (2)
- Maintain patent airway
- Clean, warm and moisten air
How does the trachea maintain a patent airway? (3)
○ C shaped cartilage rings keeps it open and unobstructed, also allows room for other structures, i.e. esophagus, trachealis muscle
○ Ends connected by bands of smooth muscle which contract to cough
○ Many elastin fibres in lamina propria and submucosa
How does the mucociliary elevator work?
Removes debris to pharynx to be swallowed and digested [clean]
○ Mucus from goblet cells and glands coats epithelium
○ Debris is trapped
○ Cilia move mucus to pharynx
How many lobes make up the lungs?
5 in total - 3 on R, 2 on L b/c heart takes up space where 3rd lobe would be
Name/describe the sup, inf, and lateral surfaces of the lungs
- Apex = superior region
- Costal surface = lateral, against ribs
- Base of lung = inferior, sits on diaphragm
What is the hilum of the lungs?
where bronchi and blood vessels enter
Describe the bronchial tree (divisions)
-> Trachea
-> 1º bronchi (L and R)
-> 2º (lobar) bronchi (to the different lobes)
-> 3º (segmental) bronchi (numerous)
-> bronchioles (very tiny)
-> branching…
-> branching…
-> branching…
-> terminal bronchioles (leave conducting zone, into respiratory zone)
Where in the resp tract is cuboidal epithelia found?
The bronchioles
What does the cartilage, if any, in the bronchi look like? Function/reason?
Plates (air resistance holds open, also nothing pushing on it this deep in body = plates are ok)
What does the cartilage in the 1º bronchi look like?
complete rings
what type of muscle is found in the bronchiole? function?
Thick smooth muscle for bronchoconstriction/dilation
What are pulmonary lobules, and what are they made up of?
Pulmonary lobules (= tiny lobes/segments) are made up of many alveoli, arranged like bunches of grapes
Describe the walls of the alveoli
Walls are very thin: simple squamous on thin basement membrane
How is the air in the alveoli keep clean?
Alveoli contain roaming macrophages to remove any debris that makes it to the alveoli
What are the 2 types of lung epithelial cells?
T1 (squamous) and T2 (cuboidal) pneumocytes
What do T1 pneumocytes do?
Form the respiratory membrane (blood-air barrier) with capillary wall and shared basement membrane
What do T2 pneumocytes do?
Secrete surfactant -> reduces surface tension of alveolar fluid
Name the layers of the respiratory membrane from alveolar space -> lumen
▪ Alveolar space
▪ Surfactant coating alveolar surface
▪ Alveolar cell layer
▪ Fused basement membranes (of alveolar epithelium and capillary endothelium)
→ Holds together so gas exchange can occur
▪ Capillary endothelium
▪ Capillary lumen
What 2 structures make up the thoracic cavity?
mediastinum (contains pericardium -> heart, vessels) and the pleural cavity (contains the lungs)
How does the pleura adhere to the thoracic wall?
Pleura sticks to thoracic wall because fluid increases adhesion
What are the boundaries of the thoracic cavity? (6)
Ant: sternum
Post: Thoracic vertebrae
Lat: Ribs/intercostal muscles
Sup: Base of neck
Inf: diaphragm
What are the 3 types of anterior thoracic joints?
sternocostal, costochondral and interchondral
Where are sternocostal joints found?
Between sternum and costal cartilage
Where are costochondral joints found?
Between ribs and costal cartilage
Where are interchondral joints found?
Joints between cartilage
Which of the ant thoracic joints are synovial
- sternocostal (except 1st = cartilaginous for rigidity at top)
- all interchondral
Which of the ant thoracic joints are cartilaginous?
- costochondral
- 1st sternocostal
What are the 2 types of posterior thoracic joints?
- costotransverse
- costovertebral
Where are costotransverse joints found?
Between rib and transverse process of vertebrae
Where are costovertebral joints found?
Between rib and body of vertebrae
Are the posterior thoracic joints synovial or cartilaginous?
synovial
What makes up the respiratory muscles?
· Diaphragm
· Intercostals
· Accessory muscles (only active when needed)
What type of muscle is the diaphragm? What type of control?
- Sheet of skeletal muscle = under voluntary control
What are the openings in the diaphragm for?
for the aorta, esophagus and inf vena cava to pass through
Describe the shape of the diaphragm when relaxed and contracted
Domed when relaxed, flattened when contracted
How does contraction of the diaphragm induce inhalation?
Contraction expands thoracic cavity, compresses abdominopelvic cavity = increase thoracic volume, decrease pressure = air in
What do the ext intercostals do? When are they used?
→ Lift rib cage up and out
→ Inspiration (quiet and forced)
What do the int intercostals do? When are they used?
→ Depress ribcage and decrease cavity
→ Expiration - forced only
What are the collective functions of the accessory muscles?
• Some increase cavity vol for forced inspiration
• Others decrease cavity vol for forced expiration
Is quiet inspiration active or passive?
active
Is quiet expiration active or passive?
passive
What do the resp muscles do for quiet inspiration?
Diaphragm contacts -> flattens
Ext. intercostals contract -> lift rib
What do the resp muscles do for forced inspiration?
Diaphragm contacts -> flattens
Ext. intercostals contract -> lift rib
+ accessory muscles contract to further expand cavity
What do the resp muscles do for quiet expiration?
Diaphragm relaxes -> domed
Ext. intercostals relax -> ribs not lifted
What do the resp muscles do for forced expiration?
Diaphragm relaxes -> domed
Ext. intercostals relax -> ribs not lifted
+ int. intercostals contract -> depress ribs
+ accessory muscles contract to further decrease cavity vol
