Gas exchange Flashcards
3 factors that affect an organisms need for gaseous exchange systems
volume
level of activity
SA:V ratio
How does an organisms volume affect their need for gas exchange systems
More layers of cells= less O2 can diffuse into the organism as it will be used up by outer cells
How does an organisms level of activity affect need for gas exchange systems
Very active animals/ animals that need heating will require larger volumes of O2 and glucose for respiration to release enough energy
What class of animals require heating?
Mammals
How does SA to V ratio affect an organisms need for exchange systems
Increase in size decreases ratio, makes gas exchange systems more necessary
Gas exchange?
Diffusion of gasses down conc grad across a respiratory surface, between an organism and its environment
Why dont unicellular organisms require gas exchange systems 2
They absorb enough O2 across plasma membrane to meet needs for respiration
Remove CO2 fast enough to prevent build up, making cytoplasm too acidic for enzyme function
Metabolic rate
Rate of energy expenditure by the body
Benefit of respiratory pigments in the blood
Increases O2 carrying capacity
Main problems to overcome with animals repairing on land
Moisture and heat retention
