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Questions
Q1.
In extreme environments organisms have characteristics that enable them to survive.
(i) Complete the sentence by putting a cross (
These characteristics are
) in the box next to your answer.
(1)
A adaptations
B alleles
C habitats
D hybrids
(ii) The photograph shows a Pompeii worm.
Pompeii worms are found in hydrothermal vents in the Pacific Ocean.
The temperature of these hydrothermal vents can be very high.
Suggest a feature that helps to protect the Pompeii worm from the extreme heat.
(1)
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(iii) Pompeii worms were discovered by French marine biologists in the early 1980s.
Explain how these biologists may have validated the evidence for the discovery of the Pompeii
worms.
(2)
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Q2.
Charles Darwin studied the variety of finches on the Galapagos Islands.
He used this information to develop his theory of evolution.
Some of the finches are shown in the diagram.
(a) (i) State the genus and the species of the large cactus ground finch.
(2)
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(ii) Suggest how the size and shape of their beaks enabled all of these types of finches to survive.
(2)
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(ii) Complete the sentence by putting a cross (
) in the box next to your answer.
Darwin's finches are an example of speciation due to
(1)
A selective breeding
B geographic isolation
C hybridisation
D the development of ring species
(b) Suggest how these species of finches could have evolved.
(3)
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(Total for Question is 8 marks)
Q3.
The dodo was a flightless bird which is now extinct.
The photograph shows the skeleton of a dodo.
The dodo lived on the small island of Mauritius. It became extinct in 1681.
Using your knowledge of natural selection, suggest why the dodo may have become extinct.
(3)
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Q4.
Taller animals may have an evolutionary advantage.
Explain how evolution by natural selection brings about changes in a species.
(3)
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Mark Scheme
Q1.
Answer
(i)
(ii)
(iii)
A – adaptations
Any one from the
following:
 large surface
area to facilitate heat
loss (1)
 insulating/fat
layer (1)
 correct
adaptation of skin /
fur / hair(1)
A explanation to
include two of the
following points:
 publishing the
evidence and results
in scientific journals
(1)
 getting other
scientists to review
their experiment /
repeat the
experiment (1)
 scientists to
investigate
hydrothermal vents
(1)
 participating in
scientific
conferences to
discuss experiment /
results (1)
 taking samples
of organisms in
hydrothermal vents
for comparison (1)
Acceptable
answers
Mark
(1)
(1)
(thick layer) of
bacteria credit
observable valid
'suggestions' from
the photo ref to not
needing to regulate
temperature as
poikilothermic (1)
use peer review
(1)
scientists searched
the ocean (1)
comparing
notes/meeting with
other scientists (1)
(2)
Q2.
Answer
a(i)
a(ii)
a(iii)
b
Genus – Geospiza
Species -conirostris
A suggestion
including two of the
following:
 (different beak
sizes/adapted)
enable different
finches to feed on
different food types
(1)
 less competition
between species (1)
Acceptable
answers
accept geospiza
accept Conirostris
eat different foods
accept comparison
between 2 beaks
and food source
more species are
able to co-exist (1)
B
geographic
isolation
A suggestion linking
three of the following
points:
 variation
between species/
beak sizes/ shapes
(1)
 due to
mutation(1)
 competition for
resources (1)
 survival of the
fittest /those best
adapted to the
environment
survived (1)
 those who
survive pass their
genes/characteristics
onto their offspring
(1)
 natural selection
(1)
Mark
(2)
(2)
(1)
(3)
Total for Question = 8 marks
Q3.
Answer
A suggestion
including 3 of the
following:
 Predation /
disease (1)
 change in
environmental
Acceptable
answers
Accept named
environmental
change / climate
change Accept food
source eaten by
other animals /
humans Accept
Mark
(3)
conditions (1)
 loss of food
source / reduced
food source (1)
 increased
competition (1)
 limited
adaptations / survival
of the fittest (1)
 unable to
reproduce /
reproduce less (1)
unable to fly so
cannot escape
Q4.
Question
Number
Answer
Acceptable answers
Mark
An explanation
linking three of the
following points:
• most individuals
within a population
vary slightly from one
another (1) • most
organisms produce
more young than will
survive to adulthood
/ overproduction (1)
• there is much
competition within
and between species
(1) • those
organisms with
advantageous
characteristics will
survive (1) • the
advantageous
characteristics will be
inherited / better
adapted organisms
are more likely to
survive to reproduce
(1)
taller animals
outcompete smaller
animals for food
survival of the fittest
the genes for the
characteristics will be
passed on / offspring
will have the desired
(3)
characteristics