Respiratory System Flashcards
why through nose
contains hairs and mucus to filter out dust particles , sinuses warm and moisten the air so it does not dry out lungs (better dissolving of water)
internal respiration
exchange of gases between blood in systemic capillaries and tissue fluid
external respiration
exchange of gases between blood in pulmonary capillaries and tissue fluid
external intercostal muscles
right outside around ribs
surfactant
water is attracted to itself due to cohesion. this is an agent that reduces surface tension which also makes it easy for alveoli to inflate and alveoli from collapsing
how is mammal respiratory system ideal
large SA, many alveoli, curved shape Thin, moist surface, internal lungs to maintain moisture, mucosa in the nasal cavity warms and moistens the air. turbinate bones provide lots of SA for filtration and warming, mechanisms to clean air, maintenance of concentration gradient by ventilation, rich blood supply for nuermous sites of exchange
compare inspiration and expiration in mammals
both use pressure gradients to move air, both pressure gradients are created by changes in volume, both use intercostal muscles, both are active processes, both rely on boil’s law
oxygen molecule to red blood cell
go through nasal cavity, over turbinate bones (get warmed and moistened), down pharynx, past epiglottis through the glottis, over vocal chords, into trachea, branch from left or right broncos, further branching into bronchioles, down into an alveolus, dissolve in moisture, diffuse into blood plasma, through red blood cell membrane, attach to iron in hamoglobin
oxygen dissociation curve
haemoglobin is primed to release more o2 at certain pressures (lower if active tissues = more o2 release). acid shift is when there is a lot of acid or low pH which means muscles are working hard which means max release of 02 (around 10% is left only). curve shifts RIGHT when in acid
oxygen and co2 levels
low oxygen goes with high carbon dioxide. high carbon dioxide increases amount of carbonic acid which lowers the pH. the brain notes this and tells the SA node to increase the heart rate which also causes vasoconstriction and dilation which means more oxygen is inhaled. more co2 exhaled which means pH returns to normal
how to protect itself
nose hairs filter particles, turbinate bones trap some dust which can be sneezed out mucus traps some, cilia move mucus down to throat to be swallowed, white blood cells can remove tiny particles, lymph ducts carry them away where WBC can get rid of them
exhalation
passive process. everything relaxes causing thoracic cavity to shrink which creates high pressure in lungs compared to outside air. this creates a gradient causing air to move outside. the alveoli have elastic collagen that stretch when you inhale. The muscles relax, the alveoli become normal which recoils the air and pushes it out too. we also have ligaments in our sternum which attach to ribcage. when you breath, you stretch that and when you relax. there is recoil helping to compress things in the lung
inhalation
(1) During the inhalation process, the diaphragm is a muscle and will actively contract (cause), which moves down and flattens out (effect), and we simultaneously contract the external intercostal muscles (cause), which rotate the rib cage outward (effect). (2) These two motions (cause) increase the volume of the chest (thoracic) cavity (effect). (3) The cohesive attraction of water molecules makes moist, hydrophilic surfaces adhere strongly to each other (necessary condition). The moist pleura of the lungs thus adheres to the moist pleura that lines the chest cavity (cause), (4) causing the lungs to increase in volume (effect) as the cavity does. (5)As the lungs expand, the air inside their alveoli occupies a larger volume (cause), and thus exerts a lower air pressure (effect).(6) Atmospheric pressure exceeds lung pressure, creating a pressure gradient (cause). (7)Air then naturally moves from the area of high pressure to the area of low pressure, the lungs (effect). The tracheal and bronchial cartilages maintain an open airway between the pharynx and the lungs. The cohesive attraction of the water molecules of the thin moist layer around the alveoli cause a surface tension, which is lowered by the surfactants produced by the alveoli. That way, alveoli require less pressure to expand and fill in with air.
