Download National 5 Biology Life on Earth Homework

National 5 Biology
Life on Earth
Homework
d) Adaptation, Natural Selection & Evolution
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Adaptation, natural selection and evolution Homework 1
1. The diagram below shows two different varieties of a moth which are found in woodland
areas.
Light coloured variety
Dark coloured variety
The dark variety was produced from the light variety by a mutation.
(a) What is a mutation?
(b) State an environmental factor that could have caused the mutation.
(c) The moths like to rest on tree bark during the day. In polluted areas tree bark tends to
be very dark. State which moth would gain an advantage in polluted areas and suggest a
reason why
2. Mutations can be neutral, confer an advantage or a disadvantage on an organism. State
if the mutations described below are neutral, confer an advantage or disadvantage on the
organism.
(a) A white rabbit was produced by two brown parents in a woodland habitat.
(b) A plant developed a resistance to insects that ate its leaves.
(c) A hedgehog was produced with half the number of spines as its parents’.
(d) Two parents with brown eyes produced a child with blue eyes.
(e) A wasp was produced without a sting.
(f) A battery hen produced one brown egg instead of the normal white coloured eggs.
3. Most mutations are spontaneous. What does this mean?
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4. An investigation into the population of dark and light coloured moths in a woodland was
carried out. The moths were captured, marked and released. 24 hours the moths were
recaptured.
The results are shown in the table below.
(a) Calculate the percentage of dark moths recaptured.
(b) Explain why there were more light coloured moths recaptured than dark moths.
(c) Why was it good experimental procedure to work out the % moths recaptured?
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Adaptation, natural selection and evolution Homework 2
1. The diagram below shows a number of Galapagos finches that have adapted to different
food sources.
(a) Which feature of the bird shown would suggest that they have adapted to different
types of food?
(b) How would these adaptations been produced?
(c) How would this type of adaptation give the bird an advantage over the other birds?
(d) What term is used to describe the differences in a population that allow it to survive in a
changing environment?
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2. Read the information below about adaptations in the small mammal called a desert rat
which is very similar to household pets known as gerbils. Answer the questions on the
following page.
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(a) Why must the desert rat be able to survive on a limited supply of water?
(b) State two structural adaptations and two behavioural adaptations that help this small
mammal to conserve water.
(c) What information in the passage would suggest that the mammal has no sweat glands?
(d) What percentage of its total water loss does it lose in its urine?
(e) What information in the passage would provide evidence to suggest that the animal’s
water intake is exactly balanced with its water loss?
(f) What other advantage might the desert gain by remaining in its burrow during the day
and hunting for food at night?
3. The table below shows the percentages of different blood groups in the UK.
a) Present the Scottish figures only as a bar chart.
(b) Copy and complete the table.
(c) Calculate the UK average percentage for each blood group and extend your table to
include these figures.
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Adaptation, natural selection and evolution Homework 3
1. The diagram below shows how animals will produce more offspring than the
environment can sustain.
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(a) Why do animals produce more offspring than the environment can sustain?
(b) Explain the term natural selection using the diagram above.
(c) State two factors that act as selection pressures on the group of rabbits.
(d) Explain how variation in the group of rabbits allows some rabbits to survive.
2. Using the terms natural selection, mutation and selective advantage to explain the
following.
(a) Over prescription of antibiotics has produced resistant bacteria.
(b) Insects have built up a resistance to some insecticides sprayed on crops.
3. What does the term survival of the fittest mean when applied to the rabbits above.
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Adaptation, natural selection and evolution Homework 4
1. What does the term speciation mean?
2. The following diagram shows speciation occurring.
(a) State an example of a geographical barrier that could separate the initial population.
(b) What is the next stage in the process after the population has been split into two by the barrier?
(c) How does natural selection play a role in this process?
(d) Assuming they are a population of rabbits state two possible selection pressures that could act
on the isolated groups.
(e) How would you know that two different species had been formed?
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3. The passage below contains information about two species of wren. A little bird found on the
Scottish mainland and the island of St Kilda. Read the passage and answer the questions.
(a) What is the isolating barrier that separates the St Kilda species from the mainland
species?
(b) Suggest one way in which the little bird could have reached St Kilda if it was too far to
fly.
(c) State two structural adaptations that the St Kilda wren shows which make it different
from the mainland species.
(d) State how the new St Kilda wren species could have been produced once it had been
initially isolated from the mainland species.
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4. The table below shows the number of different types of Darwin’s finches found on the
small island of Pina in the Galapagos Island chain.
Finch species
Warbler
Seed eater
Ground
Insect eater
Common
Number
16
4
20
8
32
(a) Use the information to complete the pie chart below.
(b) Express the number of Warbler finches with the number of Ground finches as the
smallest whole number ratio.
(c) What was the percentage of Common Finches in the total group of birds present?
(d) If the number of Finches were placed in order from the lowest number to the highest
number which Finch would be in the middle of the order?
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