Respiratory System Flashcards
Label the thoracic skeleton shown
The clavicle articulates with the scapular to form the pectoral girdle. This is involved in movement of the chest wall.
The costal cartilages connect the ribs and sternum.
Why does the diaphragm contract?
When the diaphragm contracts, the central tendon is pulled down. This increases the vertebral space within the thoracic cavity so the lungs can expand.
Where are the thoracic apertures?
draw and label the diagram to show the intercostal muscles
What are the three types of intercostal muscles?
External intercostal muscle originate from the inferior border of the ribs. Insertion: superior border of immediate rib below.
Internal and innermost intercostal muscle. Origin: costal groove of ribs. Insertion superior border of immediate rib below.
External muscle fibres point anteriorly and medially. Internal runs at right angles to the external muscle. Innermost run in the same orientation as internal but son much less regular- sometimes the muscles span 2 or more spaces, sometimes they’re completely absent.
what is the function of intercostal muscles?
External intercostal muscles (A) are most active during inspiration, they elevate ribs and sternum.Interchondral portion of internal intercostal also involved (C) in this
Internal intercostal muscles most active during expiration (B). They’re in the interosseous portion (between 2 bones), they depress the ribs and sternum
Most activity of intercostal muscle is to maintain tone in the intercostal space: ‘isometric’
label the diagram of the upper respiratory tract
What is the function of the pharynx?
Pharynx: passageway leading from the oral and nasal cavities in the head to the esophagus and larynx. This enables air to pass into airways and food to pass to the oesophagus, so pharynx chamber serves both resp and digestive functions.
It’s divided into nasopharynx, oropharynx, laryngopharynx
What is the function of the larynx
larynx controls pitch/volume of speech. Also prevents material from reaching the lower respiratory tract:
The larynx closes and pulls up slightly while eating, if this is not successful, stimulation of larynx by ingested matter produces strong cough reflex through
vagal receptors
Label the diagram of the nasal cavity
Describe the nasal cavity
Elongated, wedge-shaped spaces held open by bone and cartilage. It’s the uppermost part of resp tract
Divided into 3 regions:
Olfactory: lined by olfactory epithelium, contains olfactory receptor cells
Respiratory: rich neurovascular supply, lined by ciliated and mucous cells
Nasal vestibule: lined by skin, covered w short hair follicles
What is the lateral wall of the nasal cavity called? Describe its structure
The lateral wall of the nasal cavity is the concha, which are curved shelves of bone. It divides the nasal cavity into 4 air channels (the spaces below=meatus)
This increases SA of air during inspiration
Superior and Middle conchae are projections from the ethmoid bone. The Inferior conchae is an independent bone
Sphenoethmoidal recess (above the superior concha) receives opening of sphenoid air sinus
Describe the meatus types in the nasal cavity and the sinuses the receive
Superior meatus receives posterior ethmoid sinuses
Middle meatus surrounded by swelling called the bulla ethmoidalis. This is formed by middle ethmoidal sinus, and also recieves maxillary sinus
Inferior meatus receives nasolacrimal duct
What is this? Label it
Paranasal Air Sinuses
Describe and explain the paranasal air sinuses
Hay 4 pairs of paranasal air sinuses: ethmoidal cells, sphenoid, maxillary and frontal which open into nasal cavities
Lined by respiratory mucosa, ciliated and mucous secreting.
Lighten weight of head, humidify and heat inhaled air, increase resonance of speech, protect vital structures in event of facial trauma
The Maxillary sinus is largest, and its opening is near the top. What does this mean in terms of drainage?
The opening of the sinus is near the top. Therefore drainage of the maxillary sinus is difficult in the upright position, and drains one side at a time
What is this? Describe and label it
The larynx. This has large unpaired cartilages:
Cricoid, Thyroid, Epiglottis
And 3 smaller cartilages: Arytenoid, Corniculate, Cuneiform
The larynx is suspended from the hyoid bone via a fibroelastic membrane
It has intrinsic muscles involved in sound production
It has extrinsic muscles which move the larynx around
What is the function of the epiglottis?
Epiglottis: Leaf-shaped cartilage, protects the laryngeal inlet. It attaches to the posterior part of the thyroid cartilage
It is mobile and will move down and cover the laryngeal inlet when swallowing. This ensures food moves down the oesophagus and not the resp tract
The epiglottis is open during breathing so that air can pass into the laryngeal inlet
Describe and label the structures seen in the laryngoscopy
Piriform (Pear-shaped)recess: Common for food particles to became trapped. Coughing removes these particles.
True vocal cords produce the sound