Adaptations and Competition

Question 1

Describe in detail features and adaptations of a cactus. (4 marks)

Answer 1

Waxy coating on the surface of the cacti to prevent water loss Spine-like leaves make the cacti difficult for herbivores to eat Long, thin leaves have a smaller surface area to reduce water loss Can store water in their stem Long lateral roots maximise water absorption from the soil

Question 2

The leaves of creosote bushes: - are covered with a layer of wax - fold together during the day. Explain how the leaves of the Creosote bush help it to survive in deserts. (2 marks)

Answer 2

Reduces water loss / evaporation wax protects plant or reflects heat or keeps plant cool or unpalatable folding reduces surface area or folding reduces warming.

Question 3

Suggest two ways in which the arctic fox is adapted for life in very cold conditions.Explain how each adaptation helps the arctic fox to survive in very cold conditions. (4 marks)

Answer 3

• long / thick hair / fur (1) for insulation (1) - small ears (1) for reduced heat loss (1) - small feet (1) for reduced heat loss (1) - white fur / coat (1) for camouflage / poor emitter (1) - small surface area to volume ratio (1) reduces heat loss (1) - thick layer of fat (1) insulates / keeps warm (1)

Question 4

What is an extremophile?

Answer 4

Extremophiles are organisms that live in very extreme environments and can survive conditions that would kill most other organisms

Question 5

What do plants compete for?

Answer 5

Plants need light, carbon dioxide, water, oxygen and nutrients, such as mineral ions from the soil, and space to grow.

Question 6

What is the cooling problem for a large animal?

Answer 6

Bigger animals have a smaller surface areas compared to their volume. This means that they can conserve energy more easily, but it is also difficult to cool down.

Question 7

What is inside a camel’s hump?

Answer 7

Fat! Definitely not water!!

Question 8

Why are there more grey squirrels than red ones?

Answer 8

The greys are better competitors

Question 9

What do cactus spines help reduce?

Answer 9

Water loss

Question 10

What do animals compete for?

Answer 10

Space Food Water Mates

Question 11

How is this animal adapted for life in the desert?

Answer 11

Large thin ears to lose heat

in a cave in the hottest parts of the day

Small thin legs

Thin coat

Question 12

How does the animal below cope with sub zero temperatures?

Answer 12

Dense fur

small ears

short legs

Thick pads to withstand snow

Question 13

What does this diagram show?

Answer 13

The transpiration stream - the movement of water up a plant from the roots to the stem and out through the leaves by evaporation

Question 14

What is this an example of?

Answer 14

Decay