Name ………………………………….
ISSR MYP4 Science
Genetics
Criterion C Unit Test
Tuesday 15th January 2013
There are three sections corresponding to the three levels of Criterion C:
Level 1-2 – recall and simple problems
Level 3-4 – describing; problem-solving in familiar situations; analysing scientific information
Level 5-6 – explaining; problem-solving in unfamiliar situations; analysing and evaluating scientific information
Criterion C: knowledge and understanding of science
Achievement
level
Descriptor
Mark
The student recalls some scientific ideas, concepts and/or processes.
1–2
The student applies scientific understanding to solve simple problems.
The student describes scientific ideas, concepts and/or processes.
3–4
The student applies scientific understanding to solve complex problems in
familiar situations.
The student analyses scientific information by identifying parts, relationships
or causes.
The student uses scientific ideas, concepts and/or processes correctly to
construct scientific explanations.
5–6
The student applies scientific understanding to solve complex problems
including those in unfamiliar situations.
The student analyses and evaluates scientific information and makes
judgments supported by scientific understanding.
Criterion C Level
Level 1-2
1.
Fill in the blanks with the words in the box. You do not need to use all the words
and some words may be used more than once.
Chromosomes are found in the ____________ of the cell. The unit of inheritance is a
__________ and different versions of a gene are called _______________. The genotype
combines with environmental factors to produce the _____________.
An allele which is not expressed in a heterozygous individual is known as ______________.
The allele which determines the inherited trait is said to be _____________ .
nucleus
cytoplasm
DNA
gene
dominant
alleles
chromosome
protein
genotype
phenotype
recessive
[4]
2. The grey wolf Canis lupus has 78 chromosomes in its body cells (somatic cells). How
many chromosomes are there in a grey wolf sperm cell? [1]
A 23
B 39
C 78
D 156
3. Rabbit eye colour is controlled by a single gene, with blue eye and brown eye alleles. The
brown eye allele is dominant and the blue eye allele is recessive. What colour are the eyes
of a rabbit which is heterozygous for eye colour? [1]
A blue
B brown
C green
D not possible to say from this
information
4. Non-identical twins have the same: [1]
A inherited traits
B physical traits
C environmental traits
D none of the above
5.
Figure 1: diagram of a cell
Number 3 points to a ribosome. Describe the function of a ribosome.
………………………………………………………………………………………………
…………………………………………………………………………………………… [1]
6. Distinguish between the terms genotype and phenotype (say what each means and how
they are related.)
………………………………………………………………………………………………
………………………………………………………………………………………………
…………………………………………………………………………………………… [2]
Level 3-4
7. Sickle cell anaemia is a disease caused by a single recessive gene. The diagram below
shows how it can be inherited from parents who are both carriers with the genotype Ss.
S is the normal allele and s is the sickle cell allele.
S
s
s
Ss
ss
S
SS
Ss
a) What is the chance the child will inherit two copies of the sickle cell allele and have the
disease?
…………………………………………………………………………………………… [1]
b) What is the chance the child will be a carrier but not develop the disease?
…………………………………………………………………………………………… [1]
c) What is the chance the child will not carry the sickle cell allele?
…………………………………………………………………………………………… [1]
8. Describe the process by which the instructions in DNA build the bodies of living things.
Use a diagram to help your explanation.
……………………………………………
……………………………………………
……………………………………………
……………………………………………
……………………………………………
……………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………… [4]
9. The diagram below shows a human karyotype.
Wikipedia contributors. "Karyotype." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 21 May. 2011. Web. 14 Jun. 2011.
a) State and explain whether the karyotype shown is of a male or a female.
………………………………………………………………………………………………
………………………………………………………………………………………………
…………………………………………………………………………………………… [1]
b) Haemophilia is a genetic condition where the gene that makes the protein which is
needed for the blood to clot is mutated.
Haemophilia is X-linked, which means the gene is found on the X-chromosome.
Explain why haemophilia is more likely to occur in males than in females.
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………… [2]
Level 5-6
10. Bill is an MYP4 student with two cats: a male, called Phil and a female, called Hill.
Phil and Hill are both black but Hill has a white tail and Phil has a black tail.
One day Hill gave birth to 3 kittens. All of the kittens are black with white tails.
Hill
Phil
Bill wrote the following in his science journal:
My cats obey the laws of inheritance! Clearly the gene which controls tail
colour has two alleles, white (W) and black (w). White is dominant over
black. Phil must have the genotype ww, the kittens all have Ww and Hill has
the genotype WW. All the offspring of Hill and Phil will have white tails.
Evaluate what Bill has written.
You could consider: Does the evidence support his explanation? Does the evidence prove
his explanation? Could there be other explanations also consistent with this evidence?
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………… [4]
11. Read the text about the E. coli long-term evolution experiment and answer the
following questions.
a) Describe how evolution explains the increase in mean fitness of the populations of
bacteria in the 12 flasks.
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
…………………………………………………………………………………………… [2]
b) Suggest how the scientists could use this experiment to measure the rate of
evolution.
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
………………………………………………………………………………………………
…………………………………………………………………………………………… [2]
c) Describe one possible source of uncertainty in the experiment.
………………………………………………………………………………………………
…………………………………………………………………………………………… [1]
d) Suggest why an asexual strain of bacteria was used.
………………………………………………………………………………………………
…………………………………………………………………………………………… [1]
Evolution experiment with bacteria
The E. coli long-term evolution experiment
has been measuring genetic changes in 12
initially identical populations of Escherichia
coli bacteria since 24 February 1988. The
populations reached 50,000 generations in
February 2010.
The experimenter, Richard Lenski, and his colleagues have reported many genetic changes. Some evolutionary
changes have occurred in all 12 populations, while others have only appeared in one or a few populations.
The experiment was designed to give experimental evidence for several of the central questions of evolutionary
biology: how rates of evolution vary over time; how far evolutionary changes are repeatable in separate populations
with identical environments; and the relationship between evolution of the phenotype and genotype.
The use of E. coli as the experimental organism has allowed many generations and large populations to be studied in a
relatively short period of time. The bacteria can also be frozen and preserved, creating what Lenski has described as a
"frozen fossil record" that can be revived at any time (and can be used to restart recent populations in cases of
contamination or other disruption of the experiment). Lenski also chose an E. coli strain that reproduces only
asexually.
Each of the 12 populations is kept in an incubator in Lenski's laboratory at Michigan State University in a minimal
growth medium (liquid containing food). Each day, 1% of each population is transferred to a flask of fresh growth
medium. Under these conditions, each population experiences 7 generations each day.
The populations are also regularly tested for changes in mean fitness, and extra experiments are regularly carried out
to study interesting developments in the populations.
In the early years of the experiment, several common evolutionary developments were shared by the populations. The
mean fitness of each population increased, rapidly at first, but leveled off after close to 20,000 generations (at which
point they grew about 70% faster than the ancestor strain). All populations evolved larger cell volumes and lower
maximum population densities, and all became specialized for living on glucose (the main nutrient in the growth
medium).
One particularly striking adaption was the evolution of a strain of E. coli that was able to use citric acid as a carbon
source in an aerobic environment.
adapted from: E. coli long-term evolution
experiment. (2012, November 21). In Wikipedia,
The Free Encyclopedia. Retrieved 19:30, January
14, 2013, from
http://en.wikipedia.org/w/index.php?title=E._coli_
longterm_evolution_experiment&oldid=524121766