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Questions
Q1.
Describe the causes of variation in a population.
(2)
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Q2.
The graph shows the variation in height.
(i) Complete the sentence by putting a cross (
The range in heights of the students is due to
) in the box next to your answer.
(1)
A environmental influences only
B genetic influences only
C environmental and genetic influences
D neither environmental nor genetic influences
(ii) Describe the variation in height of these students, as shown in the graph.
(3)
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Q3.
Mike was investigating variation in a school of 650 students.
He recorded the blood group and measured the heights of the students.
The graph shows the variation in blood group.
(i) Calculate how many of the 650 students have blood group A.
(2)
number of students with blood group A =..............................................
State the type of variation shown in the graph for the blood groups of students.
(1)
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(ii)
Q4.
Human variation
Mike was investigating variation in a school of 650 students.
He recorded the blood group and measured the heights of the students.
The graph shows the variation in blood group.
(a) (i) Calculate how many of the 650 students have blood group A.
(2)
number of students with blood group A =..............................................
State the type of variation shown in the graph for the blood groups of students.
(1)
..............................................................................................................................................
(ii)
(b) The graph shows the variation in height.
(i) Complete the sentence by putting a cross (
The range in heights of the students is due to
) in the box next to your answer.
(1)
A environmental influences only
B genetic influences only
C environmental and genetic influences
D neither environmental nor genetic influences
(ii) Describe the variation in height of these students, as shown in the graph.
(3)
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(c) 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
Acceptable
answers
Mark
A description to
include two of the
following: genetic
(variation) (1) due to
mutation (1) due to
sexual reproduction /
interbreeding /
hybridisation (1)
environmental
(variation) (1)
Accept references to
different genes/DNA
Accept named
environmental
change e.g.change
in climate
Answer
Acceptable answers
Mark
C
Answer
Acceptable answers
(1)
Mark
A description
including the
following points:
• continuous
variation / data (1)
• normal distribution
curve (1) • correct
interpretation of data
from the graph (1)
bell shaped curve
e.g most common
height range 150 –
154
(3)
Answer
Acceptable answers
Mark
650 ÷ 100 (1) × 40 =
260 (1)
Answer
10% of 650 = 65 65
× 4 = 260
Acceptable answers
(2)
Mark
discontinuous
(variation)
Ignore genetic
variation (as not
shown in the graph)
Accept discrete
(1)
(2)
Q2.
Question
Number
(i)
Question
Number
(ii)
Q3.
Question
Number
(i)
Question
Number
(ii)
Q4.
Question
Number
(a)(i)
Question
Number
(a)(ii)
Question
Number
(b)(i)
Question
Number
(b)(ii)
Question
Number
(c)
Answer
Acceptable answers
Mark
650 ÷ 100 (1) × 40 =
260 (1)
Answer
10% of 650 = 65 65
× 4 = 260
Acceptable answers
(2)
Mark
discontinuous
(variation)
Answer
Ignore genetic
variation (as not
shown in the graph)
Accept discrete
Acceptable answers
(1)
Mark
C
Answer
Acceptable answers
(1)
Mark
A description
including the
following points:
• continuous
variation / data (1)
• normal distribution
curve (1) • correct
interpretation of data
from the graph (1)
Answer
bell shaped curve
e.g most common
height range 150 –
154
Acceptable answers
(3)
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