Randos 🗿
What is external respiration vs. internal respiration
External respiration:
Exchange of gases between air and blood
Internal respiration:
Exchange of oxygen and carbon dioxide gases between blood and cells of body
What is the cut-off point that splits the conducting portion vs. the respiratory portion
Conducting:
- Final structure: The terminal bronchioles
Respiratory:
- First structure: The respiratory bronchioles
What is the difference between the left and right primary bronchus, and what is its significance
The right bronchus is wider, shorter, and more vertical; more prone to obstruction
Why is inspiration vs. expiration uniquely different in terms of muscle use
Inspiration is always an active process requiring muscular contraction to expand the chest, while normal expiration is passive, relying on the elastic recoil of the lungs and muscle relaxation
What is the type of cartilage in the trachea and what is its function
hyaline cartilage; keeps trachea open and unobstructed
What are the 3 large apertures through the diaphragm, what level of the spine does it come out of, and what structure passes through each
Caval opening (T8)
For inferior vena cava
Esophageal hiatus (T10)
For esophagus
Aortic hiatus (T12)
For aorta
What is anatomic dead space in the lungs and why is it important
It is the air remaining in conducting passages, and it does NOT participate in gas exchange
The roof of the nasal cavity is formed primarily by the __________ bone, while the __________ forms the floor of the nasal cavity
ethmoid; hard palate
What is the main muscle for inspiration
the diaphragm
What type of cell provides immune protection to the respiratory system, and why are they important
Bonus Q: What are clara cells?
Alveolar macrophages are important because alveoli lack cilia to sweep pathogens
Clara cells are:
- found in bronchioles -> alveoli
- secrete Cytochrome P450 to detoxify and secrete surfactant
Define compliance, and what condition would you see high vs. low compliance
Define elasticity, and what condition would you see high vs. low elasticity
Compliance is the extent that the lungs expand
- High: Low work to expand -> emphysema
- Low: High work to expand -> pulmonary fibrosis
Elasticity is the extent that the lungs recoil
- High: Low work to recoil -> pulmonary fibrosis
- Low: High work to recoil -> emphysema
As altitude ↑:
Atmospheric pressure ↓
Gas % stays constant
BUT partial pressures ↓
less oxygen available for diffusion
Describe the order of lymphatic drainage of the lungs
pulmonary lymph nodes -> bronchopulmonary (hilar) nodes -> tracheobronchial nodes -> paratracheal nodes -> bronchomediastinal trunks -> right lymphatic duct and thoracic duct (on left)
What are the 4 types of hypoxia and what are their sources
Hypoxic hypoxia → lung disease, altitude
Circulatory hypoxia → poor perfusion
Anemic hypoxia → low hemoglobin
Histotoxic hypoxia → cells cannot use O₂ (cyanide)
Name the components of the respiratory membrane in layered order
Type I cell (pneumocyte)
Fused basal lamina (basement membrane)
Capillary endothelial cell
Endothelial cell
Red blood cell membrane
What is 2,3-Bisphosphoglycerate (2,3-BPG) and what is its significance
It is a byproduct from RBC metabolism
Binds Hb and reduces O₂ affinity, promoting O₂ release
Causes a right shift of dissociation curve
Which of the following is wrong
A. Tidal Volume (TV) = Inspiratory Reserve Volume + Expiratory Reserve Volume + Residual Volume
B. Vital Capacity (VC) = Inspiratory Reserve Volume + Tidal Volume + Expiratory Reserve Volume
C. Total Lung Capacity (TLC) = Vital Capacity + Residual Volume
D. Inspiratory Capacity (IC) = Tidal Volume + Inspiratory Reserve Volume
"A", because TV is not a sum of IRV, ERV, and RV. "A" actually represents TLC, not TV
The Dorsal Respiratory Group (DRG) houses the ______ centre, and is active in ______
The Ventral Respiratory Group (VRG) houses the ______ centre, and is active in ______
Both of these groups are housed in the ______
inspiratory; quiet breathing
inspiratory and expiratory; forced breathing
medulla oblongata (brainstem)
How does carbon monoxide poisoning happen
CO binds Hb with very high affinity → forming carboxyhemoglobin
This competes with O₂ binding sites
Describe the following changes between bronchi and bronchioles:
- Epithelium
- Goblet cells
- Cartilage
- Submucosal glands
- Smooth muscle
- Elastic fibres
We allllllll know that if FEV1/FVC is low, that we consider obstructive lung disease, right?
What if FEV1/FVC is normal or high? What would you look for next to rule out pathology?
If either FEV1 or FVC are low, then it is a restrictive lung disease
Using the following spirometry values, what are the changes you'd see in obstructed vs. restrictive lung disease
- FEV₁
- FVC
- FEV₁/FVC
- TLC
- RV
Obstructed:
- FEV₁ decreases (by a lot)
- FVC decreases
- FEV₁/FVC decreases
- TLC increases
- RV increases
Restricted:
- FEV₁ decreases
- FVC decreases
- FEV₁/FVC normal/increases
- TLC decreases
- RV decreases
The diaphragm is primarily innervated by the left and right __________ nerves. These nerves provide both __________ and __________ innervation to the central part of the diaphragm. The phrenic nerves arise from spinal cord levels __________, __________, and __________. The __________ nerves and the __________ nerve provide sensory innervation to the peripheral part of the diaphragm. Pain originating from the diaphragm may radiate to the __________ and __________ via the phrenic nerve. Pain from the diaphragm may also radiate to the __________ via the intercostal nerves.
phrenic; sensory; motor; C3; C4; C5; intercostal; subcostal; neck; shoulder; abdomen
Kiss begins a 5km run. Decide which components increase, decrease, or stay the same during this exercise
State the significance of the four different cell types of this pseudostratified epithelium