respiratory system Flashcards
what are the 3 main processes of the respiratory system?
pulmonary ventilation, internal respiration, external respiration
what is pulmonary ventilation?
breathing air in and out the lungs
what is internal respiration?
exchange of oxygen and CO2 between blood + muscle tissue.
what is external respiration?
exchange of oxygen and CO2 between lungs + blood.
what is the structure of alveoli?
it increase gaseous exchange by; having a large surface area, single cell layer of epithelial cells which decreases the distance fro gaseous exchange; moist lining of the H2O which helps dissolve and exchange CO2.
what is the pulmonary pleura?
double walled sacs with pleura fluid that helps reduce the friction between ribs + lungs.
what happens to inspiration at rest?
diaphragm contracts, external intercostal contract, diaphragm flattens, ribs + sternum move up + out, thoracic cavity volume increases, lung air pressure drops.
what happens to expiration at rest?
diaphragm relaxes, external intercostals relax, diaphragm pushed up, ribs + sternum move up + in, thoracic lung volume decreases, lung air pressure increase.
what are the inspiration muscles?
sternocleidomastoid, scalene, pectoralis major.
what are the expiration muscles?
internal intercostals, rectus abdominus, obliques
what is gaseous exchange?
exchange of gases via process of diffusion.
what is diffusion?
movement of gases from high to low pressure.
what is partial pressure?
pressure gas exerts within a mixture of gases - gases always move from high to low concentration.
what happens during external respiration during exercise?
deoxygenated blood returning to heart has higher partial pressure of CO2 + lower partial pressure of O2 - air in alveoli has high partial pressure of O2 and low partial pressure of CO2.
what happens to internal respiration during exercise?
increased dissociation of oxygen from haemoglobin to tissue because muscles demand more oxygen.
what are the 4 things that influence increased dissociation of O2?
increase in blood + muscle temperature, decrease partial pressure of O2 in muscle, increase partial pressure of CO2, bohr effect.
what is minute ventilation?
the volume of air inspired or expired per minute – TV x f =VE
what is the respiratory control centre?
a control centre in the medulla oblongata responsible for respiratory regulation.
what is the inspiratory centre
a control centre in the RCC responsible for inspiration.
what is the expiratory centre?
a control centre within the RCC responisble for expiration
what is the bohr shift?
a move in the oxyhemoglobin dissociation curve to the right caused by increase acidity in the blood stream.
what does association mean?
the combing of oxygen with haemoglobin to form oxyhemoglobin.
what does dissociation mean?
the release of oxygen from haemoglobin for gaseous exchange.
what nerves are involved in the inspiratory control centre?
intercostal nerves + phrenic nerves.
what does the expiratory centre do at rest?
it is inactive because expiration is passive.
what happens to neural control during exercise?
inspiratory – increased stimulation of diaphragm + external intercostals -stimulates inspiratory muscles which increase the force of contraction.
expiratory – stimulates expiratory muscles causing forced expiration - this drops the duration of inspiration.
What 4 things influence neural control?
chemoreceptors, proprioreceptors, thermoreceptors, baroreceptors.
