Lung Anatomy, Airways, Blood Flashcards
What are the main anatomical features of the nose?
- Air enters your body through your nose, where cilia and mucus trap particles
- Has a much larger surface area to volume ratio in comparison to mouth
How is air warmed and moistened in the nose?
- Cilia and mucus trap particles
- Humidity increases are air goes down respiratory tract
- Air is warmed in nose as it maintains core body temperature
What are the main anatomical features of the pharynx
- From your nose air moves down into the pharynx or throat which is shared with the digestive system
What are the main anatomical features of the larynx?
- Contains vocal chords which vibrate to produce sound
What are the main anatomical features of the trachea?
- Air moves from pharynx down towards lungs via trachea
- Made up of stiff rings, C-shaped of cartilage that support and protect it
- Bifurcates at sternal angle
What is the importance of stiff rings in trachea?
- Maintains patent airway -> airway is open and unobstructed
Do bronchioles have cartilaginous rings?
No. Only found in upper airways
What are the main anatomical features of the epiglottis?
- Cartilaginous flap on top of larynx
- Small flap of tissue folds over the trachea and prevents food from entering it when you swallow
What are the main anatomical features of the bronchus?
- Air moves from the trachea into the right and left main bronchi which lead inside the lungs
- Bronchi split again and go to different lobes of the lung
- Keep splitting and get smaller and smaller
What type of cartilage do smaller bronchi have?
Irregularly shaped hyaline cartilage
Where is the smooth muscle in bronchi?
Smooth muscle is only around bronchi, not alveoli
Where does gas exchange occur?
In the alveoli
Which bronchi is more vertical? Why is this important
- Right main bronchus is wider and more vertical
- Right is where foreign bodies are more likely to be aspirated
What are the main anatomical features of the lungs?
- Main organs of respiration
- Soft, spongy texture due to many thousands of tiny hollow sacs that compose them
- Pleural cavity is where the lungs sit, filled with 3ml of fluid
Lobes in the right lung
- 3 lobes: superior, middle and inferior
- 2 fissures: horizontal and oblique
Lobes in the left lung
- 2 lobes: Superior and inferior
- 1 fissure: oblique
What is the lower respiratory tract composed of?
Trachea, right lung, left lung, left bronchus, right bronchus and diaphragm
What is the upper respiratory tract composed of?
Nasal cavity, pharynx, tongue, vocal, larynx and oesophagus
Where is resistance to airflow greatest and why?
- It is greatest at the upper end of the airway
- In the lower part of the airway there are may branches and fewer and fewer molecules flow down these branches
- Whereas in the upper end of the airway there are more molecules and only one route for them to follow
What is the surface area of lungs?
80 m2
What are the volume of lungs?
6l
What happens to the lungs in the sympathetic nervous system?
- The lungs relax
- Diameter increases
- Resistance decreases
How does the gas exchange occur?
- Deoxygenated blood flows in to the pulmonary artery
- Blood flows down to the capillary bed
- There is an exchange between the alveoli and the capillary bed
- Oxygenated blood goes to the pulmonary vein
How is it possible for the gas exchange to occur?
- Capillary membranes and alveolar membranes are very thin
- Type I cells allow gas exchange
