Respiratory System Flashcards
Role of the nasal cavity
It’s where the air enters the body and it warms and moisten the air
Role of the epiglottis
Flap of cartilage that stops food entering the lungs and instead allows air to enter the lungs
Role of the alveoli
It’s where gaseous exchange takes place and they are tiny air sacs
Role of the trachea
Allows passage of air to the lungs and consists of rings of cartilage
Role of the bronchus/bronchi
Branch off from the trachea to the left and right lung
Role of the larynx
Known as the voice box , has rigid walls of cartilage and connects the pharynx to the trachea
Role of the pharynx
Known as the throat and connects the nasal cavity to the larynx
Role of the bronchioles
Connects the bronchi to the alveoli and are small airways that extend from the bronchi
What additional respiratory muscles are used during exercise?
- Internal intercostals
- Pectoralis minor
- Scalene
- Sternocleidomastoid
- Rectus abdominus
- Diaphragm
Facts about the scalene
Found in the neck and helps pull ribs up and out
Facts about the internal intercostals
They lie inside the rib cage and help draw ribs down and in for expiration
Facts about the pectoralis minor
They help raise the ribs and expand the thoracic cavity
Facts about the sternocleidomastoid
- It contracts to increase the amount of air into the lungs by lifting up rib cage , increasing volume of the thoracic cavity more and reducing pressure in the lungs more.
- It relaxes to increase the amount of air expired by pulling down the rib cage , decreasing volume of the thoracic cavity more and increasing pressure in the lungs more.
Facts about the diaphragm
Inspiration
- Contracts to increase volume of thoracic cavity and decrease pressure in the lungs
Expiration
- Relaxes to decrease volume of thoracic cavity and increase pressure in the lungs
During exercise
- Contracts harder to achieve increases in tidal volume
Expiration process during exercise
Becomes active
- Additional muscles contract to force expiration
- Rib cage moves in and down more by the internal intercostal muscles and the rectus abdominus which helps to force the diaphragm upwards
- So bigger decrease in volume of thoracic cavity
- So bigger increase in pressure in the lungs
- As a result more air is forced out faster so a faster breathing frequency
Inspiration process during exercise
There is an increase in depth and rate of breathing
- External intercostal and diaphragm contract more strongly
- Sternocleidomastoid, scalene and the pectoralis major help to pull the clavicle which is the bone that the internal intercostal muscles pull against upwards and outwards
- So larger volume of thoracic cavity
- So Bigger decrease in pressure in the lungs
- As a result more air is drawn into the lungs
Role of the external intercostal muscles
Inspiration - they contract
- Helping pull rib cage up and out , increasing volume of thoracic cavity and reducing pressure in the lungs
Expiration - they relax
- Causing the rib cage to move down and in , decreasing volume of thoracic cavity and increasing pressure in the lungs
Mechanics of breathing during Inspiration
Diaphragm and external intercostal muscles contract
Rib cage moves up and out
Volume of thoracic cavity increases
Pressure in the lungs decreases
Air is drawn into the lungs
Mechanics of breathing during Expiration
Diaphragm and external intercostal muscles relax and internal intercostal muscles contract
Rib cage moves down and in
Volume of thoracic cavity decreases
pressure in the lungs increases
Air is drawn out of the lungs
What occurs at the alveoli?
Gasesous exchange
- In capillaries the PP of oxygen is low and the PP of carbon dioxide is high
- In the alveoli the PP of oxygen is high and the PP of carbon dioxide is low
- This difference in partial pressure allows diffusion to take place
Explain the process of gaseous exchange
Gases move from high to low pressure
Oxygen diffuses into the capillaries
Carbon dioxide diffuses into the alveoli
How does a higher volume of carbon dioxide in the capillary blood of the alveoli affect gaseous exchange?
- Steeper diffusion gradient
- Gases move from high to low pressure
- PP of carbon dioxide will be higher in the capillaries than in the alveoli
- Carbon dioxide will enter alveoli faster
- More oxygen will enter capillaries
Compare the process of gaseous exchange at the muscles during exercise to resting conditions
During exercise
- Steeper concentration gradient
- PP of oxygen will be lower in muscles than at rest
- PP of carbon dioxide will be higher in muscles than at rest
- More oxygen and carbon dioxide will diffuse at a faster rate
What is tidal volume?
The amount of air inspired or expired per breath
What is the average resting value for tidal volume
400-600ml
How does tidal volume change during recovery after exercise?
It gradually decreases and it remains higher than resting values during recovery because oxygen is needed to repay oxygen debt
What is breathing frequency?
The amount of breathes taken per minute
What is the average resting value for breathing frequency?
10-15
What happens to breathing frequency after exercise is completed?
Decreases / slows down
What is minute ventilation?
Amount of air inspired per minute
What is the long term effect of regular exercise in maximum minute ventilation?
Increases
Why is minute ventilation higher during recovery than at rest?
More oxygen is needed to repay oxygen debt and remove lactic acid
More carbon dioxide is needed to be exhaled
Replenishment of myoglobin stores
Formula for minute ventilation
Tidal volume x breathing frequency
Explain why the minute ventilation of a trained athlete is lower at rest than that of a untrained individual
More efficient gas exchange at the alveoli
More mitochondria and higher aerobic capacity
Minute ventilation changes during exercise
Before - increases due to release of adrenaline (anticipatory rise)
During exercise - increases due to increased demand for oxygen
During exercise - plateau as oxygen demand meets supply
During recovery - removal of waste products
Explain why a trained athlete can reach a higher minute ventilation than a untrained athlete during exercise
They have
- Higher tidal volume
- Higher vital capacity
- Higher breathing frequency
- Increased strength of respiratory muscles
What is the expiratory reserve volume?
Volume of air available that could be expired after tidal volume
What is the inspiratory reserve volume?
Volume of air available that could be inspired after tidal volume
What is functional residual capacity?
Volume of air present in the lungs when the respiratory muscles are totally relaxed
What is vital capacity?
Total volume of air that can be inspired or expired
What is residual volume?
Volume of air that is left in the lungs
What is total lung capacity?
Total volume of lung at maximum inflation
What is the formula for TLC?
RV + VC
(residual volume + vital capacity)
Short term effects
- Increased tidal volume
- Increased breathing frequency
- Increased minute ventilation
- Increased oxygen taken in
- increased carbon dioxide expired
Long term effects
- Increased efficiency of gaseous exchange
- Increased surface area of alveoli
- Increased max breathing frequency
- Increased max minute ventilation
- Increased strength of respiratory muscles
- Increased tidal volume during exercise
- Increased vital capacity
- Increased capillarisation
Effects of a warm up
- Demand for more oxygen
- Increased breathing frequency
- Increased tidal volume to allow more oxygen to working muscles
Effects of a cool down
- Maintains elevated ventilation rate
- More carbon dioxide is breathed out
- More oxygen is breathed in to pay oxygen debt
- Keeps capillaries dilated
Inspiration at rest and during exercise is?
An active process
Expiration at rest is a?
Passive process
Expiration during exercise is a?
Active process
