HKDSE Biology – a modern approach 8
Answers to Coursebook Exercises
36
Biotechnology and Its Modern Techniques
Check your progress
36.2 Recombinant DNA technology
True or false
1.
T
2.
T
3.
F
4.
T
5.
T
(1 mark each)
(Total: 5 marks)
36.3 Polymerase chain reaction (PCR)
A.
Fill in the blanks
1.
(a)
polymerase chain reaction
2.
(b)
denaturation
(c)
annealing
(d)
extension
(e)
forensic investigations
(f)
archaeological studies
(g)
Human Genome Project
3.
(1 mark each)
(Total: 7 marks)
B.
Multiple choice
1.
B
2.
C
(1 mark each)
(Total: 2 marks)
36.4 DNA fingerprinting
Multiple choice
1.
A
2.
D
3.
D
© 2010 Aristo Educational Press Ltd.
(1 mark each)
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HKDSE Biology – a modern approach 8
Answers to Coursebook Exercises
(Total: 3 marks)
36.5 Genetically modified organisms
True or false
1.
T
2.
T
3.
F
4.
T
(1 mark each)
(Total: 4 marks)
36.6 Animal and plant cloning
A.
Fill in the blanks
1.
(a)
mammary gland
(b)
nucleus
(c)
electric current
(d)
surrogate mother
(1 mark each)
(Total: 4 marks)
B.
Question
1.
(a)
micropropagation
(b)
explant
(c)
nutrients
(d)
plant hormones
(e)
protoplast culture
(f)
plant tissue
(g)
cellulase
(h)
plants hormones
(1 mark each)
(Total: 8 marks)
© 2010 Aristo Educational Press Ltd.
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HKDSE Biology – a modern approach 8
Answers to Coursebook Exercises
Revision Exercise
Structured questions
1.
(a)
(i)
(ii)
(b)
Plasmids are circular DNA commonly found in bacteria.
(1 mark)
Plasmids can be transferred naturally between bacterial cells.
(1 mark)
restriction endonuclease
(1 mark)
DNA ligase
(1 mark)
It joins the gene for encoding human insulin with open plasmids.
(1 mark)
(c)
Escherichia coli
(1 mark)
(d)
The recombinant bacteria with the gene for encoding human insulin are grown in large
fermenters.
(1 mark)
The human insulin synthesised is collected and purified for medical use.
(1 mark)
(Total: 8 marks)
2.
(a)
The enzyme is DNA polymerase.
(b)
Step 1: Denaturation
(1 mark)
The sample of DNA is heated to about 95ºC to break and separate the double strands.
(1 mark)
Step 2: Annealing
The temperature is reduced to 50-60ºC and primers are added.
(1 mark)
Primers become attached to the complementary sequences on template DNA. (1 mark)
Step 3: Extension
The temperature is raised to about 70ºC and
(1 mark)
DNA polymerase and free DNA nucleotides are added. Duplication of the original
(c)
sections of DNA occurs.
(1 mark)
Step 4: Repetition of steps 1 to 3
(1 mark)
forensic investigations
(1 mark)
archaeological studies
(1 mark)
detection of genetic disorders
(1 mark)
(or other reasonable answer)
(Total: 10 marks)
3.
(a)
Plants are more easily genetically modified.
(1 mark)
It is because plants have less complicated genomes as compared with animals and
(1 mark)
(b)
it is easier to reproduce a large number of plants than animals.
(1 mark)
(i)
A vector is a plasmid or virus
(1 mark)
that carries and transports genes.
(1 mark)
Plasmids can replicate independently
(1 mark)
(ii)
© 2010 Aristo Educational Press Ltd.
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HKDSE Biology – a modern approach 8
Answers to Coursebook Exercises
and are transferred naturally between bacteria.
(c)
(1 mark)
The Agrobacterium Ti plasmids carry the desired genes.
(1 mark)
Cocultivation of the bacteria with plant pieces allows the desired DNA to be
transferred to plant cells.
(1 mark)
The plant cell then acquires the DNA encoding desired genes.
(1 mark)
With shoot and root regeneration, it will grow to a plant with new trait.
(1 mark)
(Total: 11 marks)
4.
(a)
Any kind of body tissue, e.g. hairs, skin, bones
OR
(b)
Any kind of body fluid, e.g. semen, saliva
(1 mark)
the PCR technique
(1 mark)
This involves the following steps:
Step 1: Denaturation
Step 2: Annealing
Step 3: Extension
Step 4: Repetition of steps 1 to 3
(c)
(3 marks)
It is useful
(1 mark)
because DNA fingerprint / information is more accurate.
(1 mark)
(Total: 7 marks)
© 2010 Aristo Educational Press Ltd.
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