Respiratory system Flashcards
What are the different basic structures of the respiratory tract starting from the nasal cavity?
Nasal cavity, nasopharynx, oropharynx, larynx, trachea, bronchi, bronchioles, alveoli
Where is the trachea located?
Above suprasternal notch, starts at C6 and ends at T 4/5 at carina
What supports the trachea’s shape?
The C-shaped rings of hyaline cartilage
What is does “anatomical dead space” refer to in relation to the respiratory tract?
No gas exchange function
How many lobes does the left lung have?
2
How many lobes does the right lung have?
3
After the trachea, what is the next structure of the airway?
The right and left main bronchus
Why is the right main bronchus slightly more vertical, shorter and wider than the left?
because the right lung does have to make space for the heart so is bigger
Where are foreign bodies most likely to end up?
The right lung due to its different shape
What does the left main bronchus split into?
Left superior and inferior lobar bronchus
What does the right main bronchus split into?
Right superior, middle and lower lobar bronchus
What do each of the lobar bronchus split into?
Segmental bronchi
What does the bronchi split into?
Conduction bronchioles, terminal bronchioles, respiratory bronchioles then alveoli
What is the main characteristic of the histology of the respiratory tract?
The pseudostratified ciliated columnar epithelium with goblet cells for mucous secretion
What three other layers of cells line the trachea?
Smooth muscle-control diameter
Submucosal glands
Fibro-elastic support
What is the difference in histology between the bronchi and trachea?
The bronchi is flatter as the height is decreased compared to the trachea
Describe the histology of the bronchiole
Epithelium is a ciliated columnar with a surrounding band of smooth muscle
Held open by surrounding lung tissue
Describe the histology of the terminal and respiratory bronchioles
Non-ciliated cuboidal epithelium
Gas exchange begins to occure
Describe the histology of alveoli
Seperated from one another be septae (alveolar wall)
What is pleura?
Membrane which covers/lines the organs within the cavity as well as the cavity walls
What is the pleural cavity?
The space between the layers of pleura- contains fluid to lubricate the movements of the organ
What is the visceral pleura?
Refers to the pleura covering the lungs
What does mediastinal pleura cover?
The pleura surrounding the middle part of the lungs, where the heart would sit between
What does the diaphragmatic pleura cover?
The part in contact with the diaphragm
What is parietal pleura?
The membranes which cover/line to cavity walls
What are the different parietal pleuras in the lungs?
Cervical, costal, mediastinal and diaphragmatic
How are the parietal and visceral layers created?
Punching a balloon analogy
What separates the two lungs?
The mediastinum
What fissure lies between the superior and inferior lobe?
Oblique
What is the lingula?
Allowing space for the heart to sit in the cardiac notch
What is the hillum?
Where the pulmonary artery, vein and lymph nodes enter the lungs
What separates the superior and middle lobes on the right lung?
Horizontal/transverse
Why is the structure of the left lung narrower and longer?
To allow space for mediastinum
How do you identify the different vessels coming into the hilum?
The cartilage surrounding them
Where does the apex of the lung begin?
Above the rib cage
What must inhalation and inspiration do?
Increase the diameters of the thorax to create a negative pressure
What does diaphragmatic contraction do?
Causes the thorax to descend, increasing its vertical diameter
What does rib elevation do?
Pushes the sternum up and forward, and the ribs outward, to increase anteroposterior and lateral diameters
What are the muscles between the ribs called?
Intercostal muscles
Describe the structure of the diaphragm
Muscular at its periphery but is tendious centrally
Left and right domes
Motor and sensory supply is by the phrenic nerve
When does a pneumothorax occur?
When air enters into the pleural cavity, results in a collapsed lung
How do you fix a collapsed lung?
A needle is inserted just above the rib to allow the lung to expand again
What is respiration?
Providing oxygen to the body and removing carbon dioxide through inhalation and exhalation
What are the superior structures of the nose?
Root, dorsum and apex of the nose
Naris (nostril)
Nasal septum
Ala of nose
What bone lies above the nose?
Nasal part of frontal bone
What bone lies under the frontal bone?
Nasal bone
What lies under the nasal bone?
Frontal process of maxilla
What lies under the frontal process of maxilla?
Lateral process
What lies under the lateral process?
Accessory nasal cartilage
What lies under the accessory nasal cartilage?
Septal nasal cartilage
What lies under the septal nasal cartilage?
Major alar cartilage
What id thr nasal septum?
A midline structure which separates the left and right nasal cavities
What lies at the front of the nasal septum?
Septal cartilage
What makes the floor of the nasal cavity?
Hard and soft palates
What is the lateral side of the nasal cavity called?
Nasal conchae
What filters, humidifies and warms air?
The 3 nasal conchae
What are the three conchae called?
Superior, middle and inferior conchrae
What does the nasal septum hang over?
The meati
What sinuses can be found in the nasal cavity?
Ethmoidal, frontal, maxillary and sphenoidal
What is clearance of mucus dependent on in the nasal sinuses?
Ciliary action, could be compromised by infection, possibly leading to sinusitis
What can happen to the septum to cause sinusitis?
It deviates
What do sinuses assist in?
Warming incoming air
What does the nasolacrimal duct do?
Enters nasal cavity to drain tears from the conjunctiva of the eye
What is anastomosis?
Connection or opening between two things that are normally diverging or branching, ie blood vessels
Where do the vessels anastamose in the nasal cavity?
Between the branches of the external and internal carotids
What are the nerves that detect smell and where can they be found?
Offactory nerves in offactory epithelium found in the offactory bulb
Roof and upper part of the lateral wall
What is the pharynx?
A tube of fibrous and muscular tissue
What are the three parts of the pharynx?
Nasopharynx- nasal cavity
Oropharynx- oral cavity
Laryngopharynx- the larynx
Describe the nasopharynx
Transports air
Divided from oropharynx by soft palate
Describe the oropharynx
Transports air plus food and fluid
Describe the laryngopharynx
Where food and fluid goes
What is the larynx?
A membranous tube suspended between cartilages. Laryngeal diameters may be altered to allow the passage of air only, and control airflow for speech and raising intra-abdominal pressure
What are the larygneal cartilages?
Epiglottic, thyroid, arytenoid and cricoid
What is the cricothyroid membrane the site of?
Emergency access to the airway
What are the key laryngeal folds?
Ary-epioglottic fold, quadrangular membrane, vestibular and vocal fold
What is the function of the ary-epiglottic fold?
Aids closure of widening of the laryngeal inlet
What do the ary-epiglottic folds form?
Laryngeal inlet
What lubricates the vocal folds?
Saccule- full of mucosal glands within the opening of the laryngeal ventricle
What are the functions of the vocal folds?
Control the laryngeal diameter for speech, coughing, sneezing and raising the intra-abdominal pressure
What muscles narrow or widen the vocal folds?
Rima glottidis
What are the main actions of the laryngeal muscles?
Close/open ary-epiglottic folds
Close/open the rima glottidis
Shorten/lengthen the vocal folds
What is the only muscle that opens the rima glottidis?
Posterior crico-arytenoid
What does the superior laryngeal nerve supply?
1 muscle and sensation above vocal cords
What does the recurrent laryngeal nerve do?
Supplies all other muscles and sensation of vocal cords and below
Where is the trachea?
Front of oesophagus, medial to carotid arteries and internal jugular veins, inferior to larynx, thyroid gland surrounds the upper portion
What does the trachea divide into?
Right and left main bronchi
