biology 3 : gas exhcange fish and insects

Question 1

name the features of exchange surfaces - 7 things

Answer 1

large sa:volume

thin

partially permable

movemnt of environment across surface(keeps concentration gradient steep)

movement of internal medium across surface(tissue fluid/blood)

located inside organisms(protection form damage)

located outside Organism(more contact with external environment)

Question 2

why do insects have a waterproof exoskeleton

Answer 2

large sa, so they lose water easily

Question 3

name 5 specialised features of insects that improve gas exchange

Answer 3

spiracles

hairs around spiracles(reduces water loss by trapping still air)

thin walls of the trachea

tracheoles highly branched(large sa)

fluid in trahceoes(moves out of tracheloes into tissues so there is faster diffusion of gasses)

air sacs(maintain concentration gradient)

abdominal movement(pumps airinto and out of tracheloes)

Question 4

explain how oxygen is transported in a insect (4 things)

Answer 4

air enters through spiracles
spiracles transfer air to trachea
then transported to the trachea, which contain fluids
gases disllove in this fluid before diffusing into cells