Gas Exchange Flashcards
1
Q
- Why does an organism need oxygen? For that to happen what do organisms need?
A
respiration = atp = respiratory surface
2
Q
- What are the properties of respiratory surfaces? (5)
A
thin = short diff pathway moist = dissolves gasses permeable = gases thru good blood supply = diff grad large SA
3
Q
- Why does amoeba not require adaptations?
A
low energy demand and large SA:V ratio
4
Q
- How does amoeba carry out gas exchange?
A
simple diffusion
5
Q
5.What is principle of SA to volume ratio? Calc SA area surface area volume
A
Size of organism increases, SA:V decreases
meaning there is small diff pathway which increases metabolic rate
a = bxh
sa = ax6
v= lxwxh
6
Q
- Does volume or surface area increase quicker, which means that adaptations are needed?
A
Volume increases quicker so adaptations needed
7
Q
- How does an earthworm increase its SA?
A
by having tubular shape
8
Q
- Where does earthworm live? Adaptation?
A
lives on land = keep epidermis moist by secreting mucus
9
Q
- What does adaption provide and where do earthworms tend to stay?
A
little protection from desiccation so earthworms stay in moist conditions
10
Q
- How does earthworm carry out gas exchange?
A
diffusion across epidermis
11
Q
- Why is it good that an earthworm has a tubular shape?
A
for high SA:V ratio
12
Q
- How does an earthworm increase efficiency of gas exchange?
A
capillary network and haemoglobin blood pigment = increases efficiency of GE
13
Q
- What other adaptations does an earthworm need? (3)
A
low metabolic rate
moist
flattened shape
14
Q
- If SA:V falls below a value, what happens?
A
GE cant happen fast enough to supply organism’s needs
15
Q
- What have larger organisms had to evolve?
A
systems and organs
