NATIONAL SENIOR CERTIFICATE EXAMINATION
NOVEMBER 2021
LIFE SCIENCES: PAPER I
Time: 3 hours 200 marks
PLEASE READ THE FOLLOWING INSTRUCTIONS CAREFULLY
1. This question paper consists of 14 pages and a yellow Answer Booklet of 16 pages
(i–xvi). Please check that your question paper is complete. Detach the yellow Answer
Booklet from the middle of the question paper. Remember to write your examination
number in the blocks provided.
2. This question paper consists of four questions.
3. Read the questions carefully.
4. Question 1 must be answered in the yellow Answer Booklet provided.
5. Questions 2, 3 and 4 must be answered in your Answer Book.
6. Start each question on a new page.
7. Number the answers exactly as the questions are numbered.
8. Use the total marks that can be awarded for each question as an indication of the
detail required.
9. It is in your own interest to write legibly and to present your work neatly.
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QUESTION 2
2.1 Read the information below on a genetic disorder known as Turner Syndrome. Use
the information in the source and your own knowledge to answer the questions that
follow.
Turner Syndrome
Turner syndrome is a disorder caused by a chromosomal mutation that affects females.
Sufferers develop symptoms that affect many organ systems. Symptoms are caused by
the loss of genetic information during meiosis, when chromosomes fail to separate
properly. Turner syndrome is not hereditary and occurs by chance.
Pregnant mothers can have a genetic test where cells from the foetus are obtained to
make a karyotype.
Figure 2.1: Karyotype of Turner Syndrome
[Adapted: <https://i.pinimg.com>]
Common symptoms of Turner syndrome include short height, delayed puberty, infertility
and heart defects. Growth hormone production and the development of the ovaries are
affected.
Turner syndrome females are treated with hormone replacement therapy. Genetic
counselling is also recommended.
[Adapted: <https://rarediseases.org> ; <https://www.genetics.edu.au>]
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2.1.1 Where in the cell would chromosomes be located? (1)
2.1.2 Give the term used to describe chromosomes numbered 1 to 22. (1)
2.1.3 Describe the chromosomal abnormality as seen in the Turner
syndrome karyotype in Figure 2.1. (2)
2.1.4 Were these chromosomes taken from a somatic cell or a gamete?
Give a reason for your answer. (2)
2.1.5 Explain clearly why Turner syndrome is not an inherited condition. (2)
2.1.6 Suggest why a karyotype analysis for genetic disorders is not routinely
offered to all pregnant women. (2)
2.2 2.2.1 Name the following referred to in the source on Turner syndrome:
(a) the gland that secretes growth hormone. (1)
(b) two ovarian hormones requiring hormone replacement therapy. (2)
2.2.2 Suggest any TWO areas of training that are important in a genetic
counsellor becoming a skilled professional. (2)
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2.2.3 Growth hormone is important in promoting skeletal and muscular
growth. It can be produced for people who do not secrete, or under
secrete this hormone using recombinant DNA technology as shown in
the Figure 2.2 below:
[Adapted: <https://img.brainkart.com/>]
(a) Name the enzyme that 'cuts' the DNA in steps 2 and 4. (1)
(b) Name the enzyme found in the process at step 5 and explain
its role in recombinant DNA technology. (2)
(c) Why are bacteria useful organisms for recombinant DNA
technology? (2)
IEB Copyright © 2021
NOVEMBER 2021
LIFE SCIENCES: PAPER I
Time: 3 hours 200 marks
PLEASE READ THE FOLLOWING INSTRUCTIONS CAREFULLY
1. This question paper consists of 14 pages and a yellow Answer Booklet of 16 pages
(i–xvi). Please check that your question paper is complete. Detach the yellow Answer
Booklet from the middle of the question paper. Remember to write your examination
number in the blocks provided.
2. This question paper consists of four questions.
3. Read the questions carefully.
4. Question 1 must be answered in the yellow Answer Booklet provided.
5. Questions 2, 3 and 4 must be answered in your Answer Book.
6. Start each question on a new page.
7. Number the answers exactly as the questions are numbered.
8. Use the total marks that can be awarded for each question as an indication of the
detail required.
9. It is in your own interest to write legibly and to present your work neatly.
IEB Copyright © 2021 PLEASE TURN OVER
,NATIONAL SENIOR CERTIFICATE: LIFE SCIENCES: PAPER I Page 2 of 14
QUESTION 2
2.1 Read the information below on a genetic disorder known as Turner Syndrome. Use
the information in the source and your own knowledge to answer the questions that
follow.
Turner Syndrome
Turner syndrome is a disorder caused by a chromosomal mutation that affects females.
Sufferers develop symptoms that affect many organ systems. Symptoms are caused by
the loss of genetic information during meiosis, when chromosomes fail to separate
properly. Turner syndrome is not hereditary and occurs by chance.
Pregnant mothers can have a genetic test where cells from the foetus are obtained to
make a karyotype.
Figure 2.1: Karyotype of Turner Syndrome
[Adapted: <https://i.pinimg.com>]
Common symptoms of Turner syndrome include short height, delayed puberty, infertility
and heart defects. Growth hormone production and the development of the ovaries are
affected.
Turner syndrome females are treated with hormone replacement therapy. Genetic
counselling is also recommended.
[Adapted: <https://rarediseases.org> ; <https://www.genetics.edu.au>]
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,NATIONAL SENIOR CERTIFICATE: LIFE SCIENCES: PAPER I Page 3 of 14
2.1.1 Where in the cell would chromosomes be located? (1)
2.1.2 Give the term used to describe chromosomes numbered 1 to 22. (1)
2.1.3 Describe the chromosomal abnormality as seen in the Turner
syndrome karyotype in Figure 2.1. (2)
2.1.4 Were these chromosomes taken from a somatic cell or a gamete?
Give a reason for your answer. (2)
2.1.5 Explain clearly why Turner syndrome is not an inherited condition. (2)
2.1.6 Suggest why a karyotype analysis for genetic disorders is not routinely
offered to all pregnant women. (2)
2.2 2.2.1 Name the following referred to in the source on Turner syndrome:
(a) the gland that secretes growth hormone. (1)
(b) two ovarian hormones requiring hormone replacement therapy. (2)
2.2.2 Suggest any TWO areas of training that are important in a genetic
counsellor becoming a skilled professional. (2)
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, NATIONAL SENIOR CERTIFICATE: LIFE SCIENCES: PAPER I Page 4 of 14
2.2.3 Growth hormone is important in promoting skeletal and muscular
growth. It can be produced for people who do not secrete, or under
secrete this hormone using recombinant DNA technology as shown in
the Figure 2.2 below:
[Adapted: <https://img.brainkart.com/>]
(a) Name the enzyme that 'cuts' the DNA in steps 2 and 4. (1)
(b) Name the enzyme found in the process at step 5 and explain
its role in recombinant DNA technology. (2)
(c) Why are bacteria useful organisms for recombinant DNA
technology? (2)
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