Lecture 1 Flashcards
What is a key organism for homeostasis?
Lungs
What are the two types of respiration?
Cellular and breathing
What are the two aspects of external respiration?
Respiration for life and for speech
Why is coordination of speech important in respiration?
So that food doesn’t enter the trachea when you are breathing - there is a mechanisms that helps with this
What are some organs in the upper respiratory system?
Pharynx, vocal cords, nasal cavity, tongue, larynx and oesophagus
What could happen if the food goes down the wrong tube?
It can cause pneumonia and different types of pathology
Define aspiration
Entry of the food into the lungs
What is the air like in the upper respiratory system?
Warmed, humidified and filtered
When is diffusion of gas more efficient?
As a saturated water phase
What type of air flow is in the nose?
Turbulent air flow and also mucus production
What does mucus do in the nose?
Traps virus particles
What is the main system of airways called
Branching airways
What are the components involved in the branching airways?
Trachea, bronchi, 2nd bronchi, bronchiole and alveoli
What is the diameter of the trachea?
20mm
What is the diameter of the alveoli?
0.3mm
How many divisions are there between the trachea and alveoli?
24 divisions
What is a type of airway epithelial cells?
Pseudo columnar epithelial cells
What are found within the cilia?
Motor units
What do the motor units do?
Repel mucus away from the lungs
What happens when you inhale viruses?
Impacted into mucus and can get destroyed by chemicals produced by the epithelial
On an electromicrograph what are the dots between the cilia?
Viruses
What do globes cells not do in sars Cov2?
They don’t support the growth of a sars cov2
What is the interferon response?
A way of killing the viruses
As you get down the sites of gas exchange what decreases?
Diameter
What is the main component for gas exchange?
The alveoli
What are capillary beds fused with?
The alveoli
What is good about the short distance between the alveoli and the circulation?
Sets up efficient diffusion for gases
Where are elastin fibres found?
They surround the alveoli
What do elastin fibres do?
Recoil pressure - they are stretched and then go back to its original form
What do collagens do?
Stiffer, but light and has a small amount of gas exchange
What are the two types of alveoli cells?
Type 1 and type 2
Describe type 1
Very thin and enable gases to diffuse through
Describe type 2
They are smaller than type 1 but are thicker and release surfactant
What do type 2 alveoli release?
A phospholipid chemical that decreases surface tension
What is a exosurf?
A protein mediated surfactant
How much of the surface do capillaries cover?
80-90%
What is fitted between elastins?
Connective tissue
What does connective tissue do?
Allows lungs to recoil when stretched
What is bronchiectasis?
Enlargement of the airways
How can bronchiectasis happen?
Chronic superlative (infection) spoils the anatomy of the lungs
How is a diagnosis of bronchiectasis formed?
On a CT scan
What is an example of airway obstruction?
Bronchiectasis
What law is stated for how air get into the lungs?
Boyles law
Increases volume = ? (Boyles law)
Pressure decreases
Decrease volume = (Boyles law)?
Pressure increases
What happens when lungs expand?
Volume increases and pressure decreases
When does atmospheric pressure decrease?
When lungs expand
What does expiration occur?
When the pressure in the lungs exceeds atmospheric pressure and the air flows out
What type of process is expiration?
Passive
What is the sealed unit that surrounds the lungs?
Pleural sac
How are alterations of pressure mediated?
By the diaphragm
What is the only muscle that works when you are sleeping?
The diaphragm
What is sometimes recruited in expiration?
Abdominal muscles and intercostal muscles
What is diaphragmatic paralysis?
When the diaphragm cannot compensate for the thoracic volume
What is FEV1?
Force expected volume in 1 second
What happens to the FEV1 when you have lung disease?
Reduces
What is MVV?
Maximum voluntary ventilation
What is FVC?
Forced vital capacity
What does the drug ivacaftor do?
Increases FEV1 but also decreases the GI symptoms
What does triple therapy do?
Increases FEV1 but also decreases the GI symptoms