Lec 1- The Respiratory System Flashcards
(38 cards)
What is the development of the Respiratory System?
It develops as a diverticulum (out pocket) from the pharynx.
It is from the primitive duct tube so it is endodermal in origin.
What is the function of the Nasal Cavity?
- induce turbulent flow (nasal conchae)
- warm and moisten inspired air.
- recover water from expired air
- speech production (phonation)
- Olfaction (sense of smell)
What is the structure of the Nasal Cavity?
- It is folded and presents a large SA of contact between the air we breathe and the vascular mucosa that line the nasal cavity.
- The nasal cavities run horizontally and this is important for passing endoscopes into nasal cavity as need to know which way to pass the tube.
What is the pathway of food?
Food goes down the oral cavity to the oesophagus.
What is the pathway of air?
Air goes down the nasal cavity down the nasopharynx to the trachea.
What are the three portions of the pharynx?
Nasopharynx
Oropharynx
laryngopharynx
What three things does the pharynx connect to?
Nasal cavity, oral cavity and respiratory tract.
What do the pharynx and larynx work together to do?
They work together to ensure that food and air enter the oesophagus and trachea respectively.
What are the different paranasal sinuses?
sphenoidal sinus - before ear
ethmoidal cells - by side of eye
frontal sinus - by eyebrow
maxillary sinus - by the cheek
What are the different components of the conducting airways?
- trachea
- primary (main) bronchi
- Secondary (lobar) bronchi
- Tertiary (segmental) bronchi
- Bronchioles
- Terminal Bronchioles
Why do the trachea have horse shoe cartilage?
This is to keep the trachea open.
- this is because you do not want the negative pressure in the trachea to collapse when breathing in.
- there is no cartilage at the back because the oesophagus sits behind the trachea, so more room for the food bolus to bulge into as it makes its way down into the stomach.
What make up the anterior and posterior wall of the thoracic cavity?
posterior - composed of vertebral bodies of the vertebral.
anterior - composed by sternum and costal cartilages.
How does the ribs articulate with the vertebrae?
By the tubercle,
- the tubercle is a little lump that contains fact and that facet along with two facets on the head of the rib are where the ribs articulate with the vertebrae.
- the superior demifacet of one vertebrae and the inferior demifacet of the one above are where they articulate with the rib.
- one rib articulates with two vertebral bodies.
What does the thoracic cavity contain?
Filled with heart and lungs.
What is there mediastinum?
The mediastinum is a big structure in the midline that separates the two lungs.
What are the two movements of the chest wall during breathing and describe them?
The bucket handle movement
- each rib is able to swing around this axis.
- —swing laterally and superiorly during inspiration.
- enables the chest to increase its lateral diameter.
- enables the volume of the chest to increase and pressure to decrease so air moves in.
The pump handle movement.
-each rib can swing superiorly, moving the sternum forward and increasing the diameter of the chest.
What is the pressure needed for air to move into the lungs>?
Alveolar pressure must be lower than atmospheric pressure for air to move into the alveoli.
Negative pressure within the thorax causes air to move into the lungs.
What is the innervation to the diaphragm?
Phrenic nerve
- made up from c3, c4 and c5
- these nerve roots keep the diaphragm alive.
- spinal cord injury affecting the neck may mean unable to breathe as may damage the phrenic nerve.
Vagus nerve
- this goes down and pierces the diaphragm which the oesophagus enters.
What is the location of the phrenic nerve?
The phrenic nerve is at front - anterior
it runs anterior to the hilum of the lungs and sits at the front.
What is the innervation of the Intercostal muscles?
it is supplied by major neurovascular bundle that runs beneath each rib.
It runs on the inferior edge of each rib.
What are the different intercostal muscles?
Internal., external and inner most.
What are the structures that pass through the diaphragm?
Vena Cava - T8 - 8 letters
Oesophagus - T10 - 10 letters
Aortic Hiatus - T12 - 12 letters
Why do you crouch over and hold onto knees when out of breath?
This is because that position is fixing the pectoralis muscles, so the origin of the pectoralis becomes the humerus so it pulls on the thorax enabling us to get a bit more air into our lungs.
Why do people with emphysema have neck in shoulder like posture?
This is because the SCM is working hard pulling the sternum and clavicle in aim to pull ribs up and give more ventilation.