1.2 - The respiratory system Flashcards
describe the passage of air.
- nose
- pharynx
- larynx
- trachea
- bronchi
- bronchioles
- alveoli
what is the pressure like in the chest cavity during inspiration?
- low pressure
what is the pressure like in the chest cavity during expiration?
- high pressure
what happens to carbon dioxide during gaseous exchange?
- diffuses from capillaries to alveolus
- high concentration in blood
- low concentration in alveolus
what happens to oxygen during gaseous exchange?
- diffuses from alveolus to capillaries
- high concentration in alveolus
- low concentration in blood
what is the function of haemoglobin?
- to combine with oxygen to form oxyhaemoglobin
- delivers it to the working muscles
what is the equation for minute ventilation?
minute of ventilation = breaths per minute X tidal volume
define tidal volume
the volume of air breathed in/out per breath
what happens to tidal volume during exercise?
increases
define inspiratory reserve volume
volume of air that can be forcibly inspired after a normal breath
what happens to inspiratory reserve volume during exercise?
decreases
define expiratory reserve volume
volume of air that can be forcibly expired after a normal breath
what happens to expiratory reserve volume during exercise?
decreases
define residual volume
volume of air that remains in the lungs after maximum expiration
what happens to residual volume during exercise?
stays the same
define minute ventilation
volume of air breathed in/out per minute
what happens to minute ventilation during exercise?
big increase
what happens to breathing during a more demanding physical activity?
increases to meet the extra oxygen demand
what is the function of the respiratory system?
to get oxygen to the working muscles and clear the body of carbon dioxide and lactic acid
what are the two aims of gaseous exchange?
- getting oxygen in the air into the lungs so that it can diffuse into the blood and be transported to the cells of the body
- the removal of carbon dioxide from the blood
define cilia
cilia are microscopic hair-like projections that help to sweep away fluids and particles
what is COPD
Chronic Obstructive Pulmonary disease
- it is a chronic and debilitating disease used to name a collection of diseases (e.g emphysema)
what is the impact of smoking on the respiratory system?
- decreases lung function
- increases breathlessness
what does smoking do to your lungs?
- damage to the cilia; causing mucus to build up (gives you ‘smokers cough’)
- irritates and damages (swells and narrows) the lining of the trachea, bronchi and bronchioles
- alveoli walls damaged; reduces efficiency of gaseous exchange
what makes up the neural control system?
- brain
- nervous system
what is the chemical control system?
- concerned with blood acidity
what do the neural and chemical control systems do?
- regulate pulmonary ventilation (aka breathing)
how does the nervous system control pulmonary ventilation?
- through parasympathetic system
- and sympathetic system
what does the respiratory centre do?
- controls the rate and depth of breathing
- uses neural and chemical control
where is the respiratory centre located?
- in the medulla oblongata
what does the respiratory centre do if there is an increase in carbon dioxide in the blood?
- it is stimulated to increase respiratory rate
what is the inspiratory centre?
- part of the respiratory centre
- responsible for inspiration and expiration
- it sends a nerve impulse via the phrenic nerve to the inspiratory muscles (diaphragm and external intercostal muscles)
- causing them to contract
after the inspiratory centre has sent out a nerve impulse what happens?
- passive expiration occurs
- due to elastic recoil of the lungs
how does the inspiratory centre help during exercise?
- chemoreceptors detect increase in blood acidity (more CO2 and lactic acid)
- send impulses to the inspiratory centre to increase ventilation
- respiratory centre sends nerve impulses down the phrenic nerve
- stimulates MORE inspiratory muscles (sternocleidomastoid, scalenes and pectoralis minor)
- as a result, breathing rate, depth and rhythm increase
what is the other part of the respiratory centre?
- expiratory centre
how do proprioceptors help the neural control of breathing?
- located in joints and muscle
- provide feedback to the respiratory centre
- to increase breathing during exercise
how do baroreceptors help the neural control of breathing?
- detects decrease in blood pressure
- to increase breathing rate
- (located in aorta and carotid artery)
what do stretch receptors do?
- prevent over-inflation of the lungs
- sends impulses to the expiratory centre , down the intercostal nerve to the expiratory muscles
- so that expiration occurs
what is adrenaline?
a natural stimulant made in the adrenal gland of the kidney, transported in the blood, affecting the nervous system
what is the hormonal regulation of pulmonary ventilation?
- release of adrenaline just before and during exercise
- brain sends an impulse to the adrenal gland
- so more adrenaline is pumped into the blood
- ready for the oxygen demand and need for carbon dioxide exchange
- therefore, breathing rate increases
Muscles used during inspiration at rest:
diaphragm
external intercostals
Muscles used during expiration at rest:
passive:
relaxation of diaphragm and external intercostals
Muscles used during inspiration during exercise:
diaphragm external intercostals sternocleidomastoid scalenes pectoralis minor
Muscles used during expiration during exercise:
internal intercostals
abdominals
