Respiratory System Flashcards
What is respiration?
the process of taking in oxygen and the removal of carbon dioxide
includes; ventilation, transport of gases, cellular/external/internal respiration
What are the different lung volumes?
tidal volume residual volume inspiratory reserve volume expiratory reserve volume minute ventilation
What is tidal volume and how does it change during exercise?
volume of air breathed out per breath
increases
What is residual volume and how does it change during exercise?
volume of air that remains in the lungs after maximum expiration
stays the same
What is expiratory reserve volume and how does it change during exercise?
volume of air that can be forcibly expired after a normal breath
slightly decreases
What is inspiratory reserve volume and how does it change during exercise?
volume of air that can be forcibly inspired after a normal breath
decreases
What is minute ventilation and how does it change during exercise?
volume of air breathed in or out per minute
(number of breaths x tidal volume)
big increase
What is vital capacity?
IRV + ERV + TV
What is the pathway of air?
nose and mouth pharynx larynx trachea bronchi bronchioles alveoli
What happens during inspiration?
intercostal muscles contract pulls ribcage up and out causes diaphragm to contract and flatten thoracic cavity gets larger causing air pressure in lungs to decrease
What happens during expiration?
intercostal muscles relax rib cage falls down and in diaphragm relaxes making it dome shaped thoracic cavity gets smaller air pressure in lungs increases
What changes in inspiration during exercise?
inspiration is assisted by; diaphragm, external intercostals, sternocleidomastoid, scalenes , pectorals
becomes an active process
What changes in expiration during exercise?
expiration is assisted by; internal intercostals, abdominal
What is gaseous exchange?
getting oxygen in the air into our lungs so it can diffuse into the blood and be transported to the cells
removal of carbon dioxide transported as carbonic acid, carbaminohaemoglobin or dissolved in plasma
How does gaseous exchange occur at the alveoli?
the ppO2 in alveoli is higher than in the capillaries
O2 moves down a conc gradient until the partial pressure is equal
oxygen has been removed from the blood by the muscles which is why the conc is lower
CO2 diffuses from blood to alveoli to be breathed out
How does gaseous exchange occur at the muscles?
the ppO2 is lower at the tissues than the blood
diffusion of O2 occurs until equilibrium is reached
CO2 diffuses from tissues to blood
How are the alveoli suited for diffusion?
large blood supply maintains conc gradient
thin alveoli epithelium for short diffusion pathway
lots of alveoli to increase surface area
How is pulmonary ventilation regulated during exercise?
neural control
chemical control
hormonal control
How does neural and chemical control work together?
neural- brain and nervous system
chemical- blood acidity
when blood acidity increases the brain is informed and stimulates the sympathetic ns to increase breathing
What does the respiratory centre do?
located in medulla oblongata
controls rate + depth of breathing (neural and chemical)
increased CO2 in blood stimulates respiratory system to increase respiratory rate
What are the areas of the respiratory centre?
inspiratory centre- responsible for in + expiration
sends nerve impulses via phrenic nerve to inspiratory muscles to contract (diaphragm + external intercostals)
What does the respiratory centre respond to during exercise?
changes in blood chemistry- increase in blood acidity
changes detected by chemoreceptors in carotid artery and aortic arch
send impulses to inspiratory centre to increase ventilation
respiratory centre sends impulses down phrenic nerve to stimulate inspiratory muscles- sternoncleidomastoid , scalenes and pectorals
this increases breathing rate and depth
What factors affect neural control of breathing?
proprioceptors- increasing breathing during exercise
baroreceptors- decrease in blood pressure increases breathing rate
stretch receptors- during exercise lungs are stretched more, expiration occurs
How does the neural/chemical control of inspiration occur?
receptors- medulla- phrenic nerve- diaphragm and external intercostals
How does the neural/ chemical control of expiration occur?
receptors- medulla- phrenic nerve- abdominals and internal intercostals
What hormonal regulation occurs?
renal glands pump adrenalin into the blood prior to exercise
increases breathing rate
How does smoking affect the lungs?
carbon monoxide binds to Hb instead of O2
nicotine restricts bronchioles
damages cilia
reduced number of alveoli- reduces gas exchange
athlete cant utilise oxygen and work aerobically
