the respiratory system Flashcards
describe the passage of air sequence
nose larynx trachea bronchi bronchioles alveoli
structure of the alveoli
1 cell thick-semi permeable membrane
short diffusion pathway
large surface area
extensive network of capillaries
tidal volume
change during exercise
the volume of air being breathed in/out per normal breath
increase
inspiratory reserve volume
change during exercise
volume of air that can be forcibly inspired (breathed in) during a normal breath
expiratory reserve volume
change during exercise
volume of air that can be forcibly expired (breathed out) after a normal breath
slight decrease
residual volume
change during exercise
volume of air that remains in the lungs after maximum expiration
remains same
minute ventilation
change during exercise
volume of air breathing in or out per minute
BIG increase
minute ventilation equation
tidal volume x respiratory frequency
what happens to the lung volume during exercise on a spirometer compared to at rest
lines become closer together and tidal volume increases, inspiratory reserve vol decreases (top), expiratory reserve vol has a slight decrease, residual volume remains the same (bottom), minute ventilation has a big increase (large line)
why does the minute ventilation increase during exercise?
because the tidal volume increases so the breathing rate is increased too
diffusion
the movement of gad molecules from an area of high partial pressure to an area of low partial pressure
partial pressure
pressure of one gas in a mixture of gases
o2&co2 in alveoli
oxygen-100mmHg
carbon dioxide-40mmHg
o2&co2 in blood vessel before diffusion at alveoli
o2-40mmHg
co2-40mmHg
o2&co2 in bv before diffusion at muscle
o2-100mmHg
co2-40mmHg
o2&co2 in bv in muscle
o2-5mmHg
46mmHg
impact of poor lifestyle choices on the respiratory system-smoking
- cigarette smoke damages the lining of the trachea, bronchi & bronchioles»cilia on surface damages»build up of mucus»smokers cough
- decrease in o2 transport»carbon monoxide in cig smoke combines with haemoglobin in rbc more easily than o2 stopping o2 combining with haemoglobin»decreases o2 carrying capacity of blood& less o2 available for respiration»breathing rate increases so breathlessness when exercising
- lung function reduced&breathlessness»caused by swelling&narrowing of lungs airways blocked with tar
- alveoli damaged»walls broken down&join together creates larger air spaces than normal»reduced efficiency of gas exchange (reduced SA)»inc risk of COPD
what is pulmonary ventilation
breathing
controlled by the sympathetic¶sympathetic nervous system
sympathetic nervous system
increases breathing rate
parasympathetic nervous system
decreases breathing rate
how is pulmonary ventilation controlled
- sympathetic nervous system
- increased concentration of co2&lactic blood
- changes detected by chemoreceptors
- chemoreceptors send impulses to inspiratory centre
- SNS impulses increase ventilation
- ventilation remains increased until blood acidity levels return to normal
- parasympathetic
(in reverse when the other way)
3 factors involved in regulation of pulmonary ventilation
- neutral control
- chemical control
- hormonal control
what is involved in controlling pulmonary ventilation
expiratory centre, respiratory centre (medulla oblongata)» phrenic&intercostal nerve, inspiratory centre
mechanical factors involved in mechanical ventilation
baroreceptors, chemoreceptors, proprioceptors, stretch receptors, hormonal-adrenaline
what are stretch receptors
prevents lungs from overinflating by sending impulses down intercostal nerve to expiratory muscle
aids the lungs to be stretched more easily during exercise
