Respiratory physiology and gas transport Flashcards
Why is surface area important in the lungs
Surface area is key in the lungs because it allows for diffusion– there is more room for diffusion with more capillaries
How many alveoli in the lungs?
300-500 million
Right vs left lung anatomy
Right has 3 lobes, left has 2 lobes (notch for the heart)
Which lung is larger
Right
Which pleura is on lungs and which is on ribs
Visceral pluera on lungs, parietal plura on wall of chest cavity
What is the function of the pleural cavity?
Space between parietal pleura on ribs and visceral plura on lungs- decreases friction.
Where is the pressure between the lungs and pleural cavity?
MUST have less pressure in the pleural cavity than the lungs at ALL times
What happens if the pressure changes between the lungs and pleural cavity (and what is it usually)
Typically: Pressure in lungs is > than pressure in pleural cavity
When pressure in pleural cavity >than in lungs=pneumothorax.
What kind of pressure is the pressure between lungs and pleural cavity called
Negative pressure- MUST have more pressure in lungs than pleural space
Path of air from nose to smallest structure
Nose–>pharynx–>larynx–>trachea–>main (primary) bronchus–> terminal bronchiole–>respiratory bronchiole–>Alveolar sac–>Alveoli
Main function of nose
filters out bactera, viruses, dust
What is nasal mucus important for
Warms and moistens air
What is the makeup of blood supply and epithelium in the nose
Rich blood supply, thin epithelium– gives quick access to blood (good for drugs)
Why is the nose better at handling cold dry air than the mouth?
Nose has mucus, which is better at cold dry air because mouth just has saliva
Tissue makeup of trachea
Muscular tube with mucous membrane, supported by hyaline cartilage ring
- Made up of pseudostratified, cilliated epithelium from nose–>Top of bronchus
What is the function of hyaline cartilage in trachea
every time we breathe in, we create negative pressure in the trachea. The cartilage keeps our trachea from collapsing.
Additionally, if you swollow something too big in your esophagus, it expands, which could make trachea collapse (but hyaline prevents)
What is a key feature of and what is the inner layer of primary bronchi called
Has cartilage rings in it
Inner layer is ciliated epithelium
How many divisions are there in bronchial tree
23 divisions
Describe the anatomy of bronchioles (muscle, cartilage, etc)
- No cartilage, smooth muscle to change airway size
What occurs in SNS activation of the bronchioles and which receptor is responsible
Beta 2 receptors are activated, causing SNS activation and dialation of bronchioles (via relaxation of smooth muscle). Further inhibts goblet cells to inhibit secretions of mucus.
Describe PNS activation of bronchioles
Constrict airway size, contract smooth muscles
What is the last passageway before the alveoli
alveolar ducts
What are alveoli sourrounded by? Why?
- Sourrounded by capillaries, function is gas exchange
Function and structure of type 1 pneumocytes
They are the alveoli!
Simple squamous epithelium (1 layer, very flat) (epithelial tissue)
Function and structure of type 2 pneumocytes
Surfactant secretion- play protective roles
What types of organelles are on the surface of alveoli
Macrophages- present for protection
What type of cell type lines the nose through bronchus
pseudostratified, cilliated epithelium
Where can you find psuedostratified, cilliated epithelium?
Top of nose thorough broncus
What type of cells are at the top of the bronchioles
simple columnar epithelial
What type of cells are found in bottom of bronchioles
simple cuboidal
What type of cells are in alveoli
simple squamous type 1 pneumocytes
Where can you find simple columnar epithelial tissue
top of bronchioles
Where can you find simple cuboidal tissue
bottom of bronchioles
Describe club cells function and structure
Progenitor cells- replace epithelal cells along the way- noncilliated
What defense secretions does the immune system have
IgA in mucous
Collectins (activate cells of innate immune system)
Defensins ( proteins- interact with pathogens and destroy them)