baisics Flashcards
what do all living organisms exchange gases with
surrounding environment
defenition of gas exchange
movement of gasses between the organism and the environment
what is a respitory surface
occurs due to diffusion of gasses over a part of the whole surface of the body
what 4 features should the respiratory surface have
1 - large surface area
2 - thin (short diffusion pathways)
3 - moisture
4 - effective transport system
how do they overcome problems with size increases
thin
permeable
moist
large surface area
concentration gradient
what is amoeba a example of
simple uni cellular organism
what is the respiratory surfae in a amoeba
cell membrane
what is the charecteristics of ameoba cell membrane
thin
moist
short diffusion pathway
what can uni cellular organisms rely on that multi cellular cant
diffusion alone
(large needs blood pigment)
where does gas exchange happen in worms
doesn’t have a specialised organ
surface of the whole body
BUT does have a closed blood system
what is the relationship between surface area to volume and size
bigger the organism the smaller the surface area to volume ratio
what do insects have
number of tubules called trachea which are full of air
what do water insects and fish have
respiratory surfaces called gills
what do birds, reptiles and mammals have
lungs
what have stuff with lungs also developed
internal transport system
respiratory pigment
what is a internal transport system
provided by circulatory system for moving gases between respirating cells and the respiratory surface
what is respiratory pigment
increases the ability of the blood to transport oxygen
how does gas exchange in insects occur
through paired holes called spiracles
what happens to fluid levels in tracheoles in insects during flight
decreases to provide more surface area for gas exchange
what ventilates the trachial system in insects
compression and expansion of the abdomen
what opens and closes to allow air into tracheal system
spiracles open and close
how much denser is water than air
1000
how many times more sticky is water than air
100
does water or air have a higher concentration of oxygen
air
