The Respiratory System Flashcards
What does the respiratory system do?
Allows the body to extract oxygen from the air into the blood, while offloading carbon dioxide from the blood into the air.
What is the main function of the nasal cavity?
Acts as a filter to prevent larger objects that we inhale from reaching the lungs
What other system is the pharynx a passageway?
Digestive and respiratory systems
What is the main function of the larynx in the respiratory system? What else does it do?
Contains vocal cords which produce sound
True or False: The trachea extends into the lungs
False - the primary bronchi do
What are the parts of the bronchial tree? (8)
Primary bronchi, secondary bronchi, tertiary bronchi, bronchioles, terminal bronchioles, respiratory bronchioles, alveolar ducts, alveoli
What do the pleura do?
Surrounds the lungs (double layered membrane) they provide a smooth and friction-less space which the lungs can expand and recoil during breathing
The thorax and abdomen are separated by what muscle?
The diaphragm
What do the alveoli do?
Thin walled sacs that contain air which diffuse air into the capillaries
How thick are the alveoli walls? Why is this important?
1 cell. Enables optimal gas exchange via diffusion
Breathing in is also called?
Inspiration
Breathing out is also called?
Expiration
What is the main goal of breathing?
Allows the body to extract oxygen from the air into the blood, while offloading carbon dioxide from the blood into the air
Where does external respiration occur?
In the lungs, between the blood and the air
Where does internal respiration occur?
Throughout the body between the blood and other cells
What is the term used to describe the relationship between the pressure inside and outside the lungs?
Pressure gradient
Inspiration increases or decreases the volume in the lungs?
Increases - the intercostal muscles contract while the diaphragm contracts downward
What happens to the pressure inside the lungs during inspiration?
Creates negative pressure which draws air into the lungs like a vacuum
Expiration results from the diaphragm and external intercostal muscles contracting/relaxing?
Relaxing
What happens to the pressure and volume inside the lungs during expiration?
The lungs are compressed and volume decreases
What are chemoreceptors?
They monitor the oxygen content of the blood when oxygen is low
Where are the chemoreceptors located?
In the carotid arteries and aortic arch
What happens when chemoreceptors detect low oxygen levels?
They signal to the respiratory control centre which increases the rate and depth of breathing
Is the respiratory system voluntary or involuntary?
Involuntary with an exception, can be partially overridden by input from the cerebral cortex eg. Holding breath
What factors can influence respiration?
Exercise, external factors eg high altitudes, ageing, nervous factors eg fight or. Flight and temperature
What is an example of airway resistance?
Asthma (inflamed airways and mucous is produced)
How is airway resistance typically determined?
Friction or drag that air encounters (diameter of airway, mucus, foreign particles)
Pressure gradient moves from:
High partial pressure to areas of low partial pressure
