RS Anatomy Flashcards
What structures are in the upper respiratory tract?
- Nasal passages (nasal cavity)
- Pharynx
- Larynx (level of glottis)
What structures are in the lower respiratory tract?
- Sub-glottis & trachea
- Bronchi
- Bronchiole
- Alveolus
What do the nasal passages include?
- Nasal vestibule
- Nasal cavities
Nasal cavities have 2 parts: Olfactory region (for smell; FYI) & Respiratory region (area that ‘conditions’ the air)
What does the pharynx include?
- Nasopharynx (opens into nasal cavity)
- Oropharynx (opens into oral cavity)
- Laryngopharynx (opens into larynx)
Pharynx is a fibromuscular tube
What does the larynx include?
- Laryngeal inlet
- Cavity of larynx
- Glottis
What is found in the nasal vestibule?
Aka nostrils
- Skin
- Hair (vibrissae): Trap bigger dust particles
Where are the turbinates found?
In the nasal cavity
What is the function of the turbinates?
- Slow down air flow to enable air conditioning & filtering
- Bony structures
turbinates = rmb ‘turbulence’ so slow down = give more time for the cells of mucous mbn
What lines the lateral walls of the nasal cavity?
Respiratory epithelium
What does the respiratory epithelium consist of?
- Ciliated Pseudostratified columnar epithelium (move mucus/foreign particles)
- Goblet cells : secrete mucin; when mixed with water = mucus
- Sensory cells (sneeze/cough)
What does the respiratory epithelium do?
- Mucus produced by goblet cells trap dust/particles/bacteria
- Cilia moves trapped dust to larynx to be coughed/spat out
Basically, traps and remove bad things from the air that entered your body
What is present beneath the respiratory epithelium and what is the function?
Within the lamina propria (beneath epithelium):
- Seromucous glands = secrete watery secretions to humidify air
- Blood vessels = warm the air
What is the function of the soft palate?
Seals off the nasopharynx from the oropharynx in the presence of food (so food X go up nasopharynx)
What is the epiglottis and what does it do?
- Elastic cartilage
- Epiglottis bends & seals off laryngeal inlet (X aspiration)
What are the 4 mechanisms that prevent aspiration?
- Epiglottis: Bends & seals off laryngeal inlet
- Glottis: Closes off when there is food
- When eating/swallowing, you stop breathing for 1 second
- Larynx and trachea are pulled up = more space for oesophagus
What does the vocal cords/glottis do?
When there is food, the glottis is closed off
Opens when breathing
Structure of larynx
- Cartilaginous assembly connected by ligaments & membranes
- Epiglottis forms the inlet
- Thyroid & Cricoid cartilages bound the cavity
What are the functions of the larynx?
- Prevent. asphyxiation (main function)
- Vocal production (phonation): vocal cords (folds)
What causes the vocal folds to move?
Muscles
- Vocal folds pulled away - abduction
- Vocal folds close together - adduction
What is the structure of the trachea?
- C-shaped cartilage rings - aka Hyaline cartilage
- Two ends of the “C” connected by smooth muscle - trachealis muscle at the back of body
At which vertebrae does the trachea divide?
Bifurcation happens at rib T4 (thoracic rib 4)
At which rib does the trachea start and end?
Starts at C6 (cervical vertebrae 6) and ends at T4 (thoracic vertebrae 4)
What connects the one C-shaped hyaline cartilage to the next?
Fibroelastic tissue
What are the 3 branches from the arch of aorta?
- Brachiocephalic artery
- Left common carotid artery
- Left subclavian artery
What does the brachiocephalic artery split into?
- Right common carotid artery
- Right subclavian artery
Where does the arch of aorta cross the trachea?
Crosses the trachea on the left side of the trachea bifurcation
What does the lamina propria consist of?
- Connective tissue (a bit)
- Seromucous glands
- Blood vessels
- nerve endings
What are the differences between the right and left main bronchus?
Right main bronchus is
- more vertical
- wide in diameter
- shorter in length
Foreign bodies more likely to be aspirated into the right side
Most common side of obstruction
What is the conducting zone?
- Space between the nose to terminal bronchiole
- No gas exchange: anatomical ‘dead’ space
- Primary source of airway resistance (bronchi)
Where is the respiratory zone?
- respiratory bronchiole to alveoli
- gas exchange occurs here (acinus)
Structure of the bronchus
- Respiratory epithelial lining
- Smooth muscle beneath the epithelium
- Broken cartilage in walls - so doesn’t collapse
- Seromucous glands
How is the structure of the bronchus affected in asthma?
There is airway resistance in the medium bronchus (in everyone)
Smooth muscles in bronchus contracts = diameter smaller
Structure of the bronchiole
- Lumen diameter ≤ 1 mm
- No cartilage in walls
- Sparse glands & goblet cells
- Low columnar epithelium (X pseudostratified)
- Club cells in the epithelium: replaces goblet cells in epithelium
- Smooth muscles in the walls (more abundant)