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
How is the lower resp tract arranged?
The trachea bifurcates into the left and right main bronchus at the sternal angle. The bifurcation is called the carina
This bifurcates into 2 left lobar bronchi and 3 right lobar bronchi
These subdivide again into segmental bronchi and eventually divide into the bronchioles and alveoli
Describe the Trachea
Mobile cartilaginous and membranous tube, 11cm long, 2.5cm diameter
Fibroelastic tube kept patent by U-shaped bars (rings) of hyaline cartilage
Posterior free ends connected by smooth muscle called trachealis. This ensures passage of food down the posterior oesophagus is not restricted
Describe the bronchi
Right main bronchus is wider and shorter (2.5cm length), almost a continuation of the trachea
Left main bronchus is narrower, longer and more horizontal (5cm length)
Inhalation of foreign bodies is more likely to enter right bronchus, passing into middle or lower lobe bronchi
What are uses of bronchoscopy?
Bronchoscopy: enables examination of trachea to carina:
Experience permits view of lobar and even segmental bronchi
Can be used for biopsy of mucous membrane and removal of inhaled foreign bodies
Tracheostomy may be used in severe cases to re-establish an airway. This is an opening created at the front of the neck so a tube can be inserted into the trachea to help breathing.
Describe the bronchial tree
Hay bifurcation of the trachea behind the arch of the aorta into left and right principle bronchi
Bronchi divide dichotomously (in 2), creating millions of terminal bronchioles that terminate in respiratory bronchioles
Each respiratory bronchiole divides into 2-11 alveolar ducts that enter alveolar sacs
Label the bronchial tree
Label the lobes and fissures of the lungs
Hay 3 lobes on the right and 2 on the left. It is thought that the left ventricle projects over onto the left chest cavity which is why we don’t have a left middle lobe
Label the surfaces and borders of the lung
Describe the Hilium in the right lung
Root/Hilium of each lung is a short, tubular collection of structures attaching the lung to the mediastinum.
It’s covered by a sleeve of mediastinal pleura.
Within each root is: Pulmonary artery, pulmonary veins (2), main bronchus, bronchial vessels, nerves and lymphatics
What is the pulmonary ligament?
Pulmonary ligament: fold of pleura that projects inferiorly from the lung root. The function is to:
Stabilise inferior lobe
Permit movement during respiration so that our vessels dosent become compressed surrounded by tissue
Which nerves pass through the lung root?
Vagus nerves pass immediately posterior to lung root. It comes from the brain, through the thorax and into the abdomen.
Phrenic nerves pass immediately anterior to the lung root. The phrenic nerve supplies the diaphragm.
What consits of the hard palate?
The hard palate is formed of two bones: the palliative process and posteriorly, the horizontal plate of the palliative bone.
How is the tongue divided?
The tongue is divided into the anterior 2/3 (oral) and posterior third (pharyngeal). Terminal sulcus is the distinct V shape at the back of the tongue which defines the boundary between oral and pharyngeal part of the tongue.
Between diagonal filiform hay fungiform papillae which have tastebuds in them.
What are the bronchopulmonary segments ?
An area of lung supplied by a segmental (tertiary) bronchus and pulmonary artery branch
Each is shaped like an irregular cone. The apex (purple) faces the lung root. The base (blue) is at the pleural surface
Functionally independent. Smallest area that can be isolated and removed sin affecting adjacent lung regions
Usually 10 in RL, 8 in LL as some of them fuse in left lung
Label this diagram- what is it?
Describe what is labelled in this left lung
Pulmonary ligament: fold of pleura that projects inferiorly from lung root
- Stabilises inferior lobe
- Prevents constriction of vessels during respiration
- Vagus nerves pass immediately posterior to lung root and phrenic nerves immediately anterior
What is this? Label it
What is this? Label it
Describe the anatomy of the trachea
- Enters superior thoracic aperture, connecting the root of the neck with the thorax
- Lies obliquely, tilted anterosuperiorly
- The superior pleural cavities, which surround the lungs, lie on either side of the entrance to the mediastinum
Label this diagram of the trachea
Describe the pleura
Smooth membrane which secretes serous fluid
Two membranes of epithelial cells
Line and enclose body cavities
One continuous layer in each cavity
Parietal lines body walls and Visceral lines organ layers
In between the 2 layers of pleura hay a potential space, or pleural cavity.
Using a diagram, differentiate between visceral and parietal pleura
Label the divisions of the parietal pleura
Label this and say what it shows
Shows further Divisions of Parietal Pleura
What are recesses of the pleural cavity?
- Costodiaphragmatic recess: Between costal and diaphragmatic parietal pleura. Occupied by lungs during inspiration
- Costomediastinal recess: Between costal and mediastinal parietal pleura. Occupied by anterior border of lungs during inspiration
What is the bronchial circulation?
- It is part of the circulatory system that supplies nutrients and oxygen to the bronchi, lung roots, visceral pleura and supporting lung tissue
- Consits of bronchial arteries which rise from the descending aorta, and bronchial veins. The veins drain into the azygous vein (R) and accessoryhemiazygous vein (L)
- The dual blood supply to the lungs via the bronchial and pulmonary systems means the lungs are more resistant to infarction
Describe the bronchial arteries
These supply bronchi and connective tissue. End at the level of the respiratory bronchioles
- 2 in left lung (sup/inf), 1 in right lung
- Left arise direct from aorta
- Right arise from 3rd posterior intercostal artery
Label these and explain what it is
Label this diagram and say what it is
Bronchial veins.
- Return blood from larger bronchi and structures of the lung root
- Carries waste products away from lung tissue cells
- Only carry 13% blood flow – rest is returned to the heart via the pulmonary veins
- Right side drains into azygous veins
- Left side drains into accessory hemiazygous vein
Describe lymphatic drainage of the lungs
- Lymphatic vessels of the lung arise from 2 lymphatic plexuses:
- Superficial - drains the lung parenchyma
- Deep – drains the structures of the lung root
- Both empty into tracheobronchial nodes – located around the bifurcation of the trachea and main bronchi
- Then pass into the bronchomediastinal trunks
