Paper 2 H - SAMPLE SET 1 Q22 Answers
22) The rock pocket mouse is a small grey coloured mouse that lives in Mexico.
These mice are the main food for owls.
Rattlesnakes also feed on these mice.
The mice get most of their food from grass plants and grass seeds.
(a) (i) How many trophic levels are there in the feeding relationships described? [1]
(ii) Draw a labelled pyramid of biomass for these feeding relationships. [2]
(b) Scientists have been studying an area of Mexico that is covered with black rocks.
Most of the rocks in other areas are grey.
The black rocks were formed about 1000 years ago when a volcano erupted.
They found that most of the mice that lived on this rock were black in colour.
(i) Explain how the population of mice in this area became mostly black. [5]
(ii) Changes to populations of mice, bacteria and insects can happen over fairly short time periods. Explain why changes to species such as humans take much longer. [2]
(Total for Question 22 = 10 marks)
Rattlesnakes also feed on these mice.
The mice get most of their food from grass plants and grass seeds.
(a) (i) How many trophic levels are there in the feeding relationships described? [1]
(ii) Draw a labelled pyramid of biomass for these feeding relationships. [2]
(b) Scientists have been studying an area of Mexico that is covered with black rocks.
Most of the rocks in other areas are grey.
The black rocks were formed about 1000 years ago when a volcano erupted.
They found that most of the mice that lived on this rock were black in colour.
(i) Explain how the population of mice in this area became mostly black. [5]
(ii) Changes to populations of mice, bacteria and insects can happen over fairly short time periods. Explain why changes to species such as humans take much longer. [2]
(Total for Question 22 = 10 marks)