6.4 GAS EXCHANGE Flashcards
ESSENTIAL IDEA
the lungs are actively ventilated to ensure that gas exchange can occur passively
VENTILATION
movement of air into and out of the lungs in two stages
inspiration and expiration
WHAT IS VENTILATION CONTROLLED BY?
the movement of the diaphragm and ribcage
GAS EXCHANGE
the exchange (diffusion) of oxygen and CO2 to and from the blood at the alveoli and the respiring tissue
CELL RESPIRATION
this is production of ATP at the cellular level (mitochondria)
aerobic respiration uses oxygen
anaerobic does not
LARGER ORGANISMS HAVE
adaptations that reflect their environmens
SMALLER ORGANISMS CAN
exchange gases directly with their surroundings through diffusion
LAND BASED ANIMALS HAVE EVOLVED AN
internal ventilation system which allows for gas exchange with the blood
WHY DO WE NEED AN INTERNAL VENTILATION SYSTEM?
to maintain a large concentration gradient with the alveoli and the blood
WHAT IS OUR CONCENTRATION GRADIENT?
high CO2 conc and low O2
BREATHING OUT
increases the conc gradient of CO2 between the blood and alveolus so CO2 will diffuse out
BREATHING IN
increases the conc gradient of O2 between the alveoli and blood
so it diffuses into the blood
VENTILATION
maintains concentration gradients of O2 and CO2 between air in alveoli and blood flowing in adjacent capillaries
FOR GAS EXCHANGE TO BE EFFIECIENT
high concentration gradient must be maintained in the alveoli
IF ALVEOLI WERE NOT VENTILATED
equilibrium would be reached and no gas exchange would occur
INTERCOSTAL MUSCLES
control the movement of the ribcage
THE VENTILATION SYSTEM DIAGRAM
https://image.slidesharecdn.com/biok6-160301001719/95/bioknowledgy-presentation-on-64-gas-exchange-9-638.jpg?cb=1457352468
INSPIRATION
PRESSURE CHANGE
decrease