# Life Sciences Grade 12 P1 Gauteng Mock 2021 QP (Eng)

> Grade 12 Life Sciences Paper 1 question paper from the Gauteng Mock Exam 2021 (English), 17 pages. Read online or download the free PDF.

- Page: https://www.hlayiso.com/library/gr12-life-sciences-p1-english-2021-preparatory-question-paper/b2fee377-3453-4de5-b563-b1a1aa1cde43
- Updated: 2026-09-27
- Subject: Life Sciences
- Grade: Grade 12
- Language: English
- Document type: Question paper
- Year: 2021
- Exam period: Gauteng Mock Exam
- Paper: 1
- Curriculum: CAPS
- Pages: 17

Breadcrumbs: [Home](https://www.hlayiso.com/) › [Library](https://www.hlayiso.com/library) › [Grade 12](https://www.hlayiso.com/library/grade-12) › [Life Sciences](https://www.hlayiso.com/library/grade-12/life-sciences) › [Life Sciences Grade 12 P1 Gauteng Mock 2021 QP (Eng)](https://www.hlayiso.com/library/gr12-life-sciences-p1-english-2021-preparatory-question-paper/b2fee377-3453-4de5-b563-b1a1aa1cde43)

## About this document

Life Sciences · Grade 12 · Gauteng Mock Exam · 2021 · English. Question paper, 17 pages. Read online or download the PDF.

Read it free online on the page above; download the PDF from there.

## Document text

Text extracted from the PDF. Layout, diagrams and tables may not survive extraction.

### Page 1

Downloaded from hlayiso.com

               GAUTENG DEPARTMENT OF EDUCATION
                      PREPARATORY EXAMINATION

                              2021
                               10831

                           LIFE SCIENCES

                              PAPER 1

TIME:      2½ hours

MARKS: 150

17 pages

                                                 P.T.O.

### Page 2

Downloaded from hlayiso.com
                                         LIFE SCIENCES                                     2
                                         (Paper 1)                             10831/21

INSTRUCTIONS AND INFORMATION

1.   Answer ALL the questions.

2.   Write ALL the answers in the ANSWER BOOK.

3.   Start the answers to EACH question on a new page.

4.   Number the answers correctly according to the numbering system used in this
     question paper.

5.   Present your answers according to the instructions of each question.

6.   Make ALL drawings in pencil and label them in blue or black ink.

7.   Draw diagrams, flow charts or tables only when asked to do so.

8.   The diagrams in this question paper are NOT necessarily drawn to scale.

9.   Do NOT use graph paper.

10. You may use a non-programmable calculator, protractor and a compass where
    necessary.

11. Write neatly and legibly.

                                                                                          P.T.O.

### Page 3

Downloaded from hlayiso.com
                                           LIFE SCIENCES                                  3
                                           (Paper 1)                          10831/21

SECTION A

QUESTION 1

1.1   Various options are provided as possible answers to the following questions.
      Choose the correct answer and write only the letter (A – D) next to the question
      number (1.1.1 to 1.1.8) in the ANSWER BOOK, for example 1.1.9 D.

      1.1.1   Which part of a neuron transmits an impulse towards the cell body?

              A     Dendrite
              B     Cytoplasm
              C     Axon
              D     Nucleus

      1.1.2   What is the gland that secretes insulin called?

              A     Thyroid
              B     Hypothalamus
              C     Pituitary/Hypophysis
              D     Pancreas

      1.1.3   Which of the following structures in an amniotic egg protects the
              developing embryo from physical injury?

              A     Yolk sac
              B     Chorion
              C     Allantois
              D     Shell

                                                                                         P.T.O.

### Page 4

Downloaded from hlayiso.com
                                             LIFE SCIENCES                            4
                                             (Paper 1)                    10831/21

1.1.4   Which labelled structures indicate the place where fertilization and
        implantation occur?

        A       A and D
        B       A and B
        C       B and C
        D       B and D

1.1.5   Study the following factors related to reproduction in females:

        (i)     When progesterone levels peak, FSH and LH levels are low.

        (ii)    Ovulation occurs at around day 14.

        (iii)   When fertilization occurs, FSH levels remain high.

        (iv)    Oestrogen and progesterone produced by the ovaries during the
                ovarian cycle influence the uterine cycle.

        The correct statements are ...

        A       (i), (ii), (iii) and (iv).
        B       (i), (iii) and (iv).
        C       (i), (ii) and (iii).
        D       (i), (ii) and (iv).

                                                                                     P.T.O.

### Page 5

Downloaded from hlayiso.com
                                     LIFE SCIENCES                                       5
                                     (Paper 1)                            10831/21

1.1.6   Which of the following represents the correct sequence of development,
        after fertilization has taken place?

        A       Ovum → Zygote → Blastocyst → Morula → Foetus
        B       Zygote → Morula → Blastocyst → Foetus

        C       Ovum → Zygote → Morula → Blastocyst → Foetus
        D       Zygote → Blastocyst → Morula → Foetus

Use the diagram below to answer the QUESTION 1.1.7 and QUESTION 1.1.8.

                                            Middle Piece         Head

            A

                                                   B

                                                                C     D

1.1.7   The only part of the sperm cell that enters the ovum during fertilization
        is …

        A       part D.
        B       part C.
        C       part B.
        D       part A.

1.1.8   The parts of the sperm cell that assist the sperm with movement are …

        A       parts A, B and C.
        B       parts, A and D.
        C       parts A and B.
        D       parts A, B and D.

                                                                            (8 x 2)   (16)

                                                                                       P.T.O.

### Page 6

Downloaded from hlayiso.com
                                              LIFE SCIENCES                                     6
                                              (Paper 1)                         10831/21

1.2   Give the correct biological term for each of the following descriptions. Write only
      the term next to the question number (1.2.1 to 1.2.5) in the ANSWER BOOK.

      1.2.1   A condition caused by the lens of the eye becoming cloudy

      1.2.2   The part of the nervous system that responds when a person gets a
              fright

      1.2.3   A phenomenon where the main central stem displays more growth than
              the side stems, at the tip of a tree

      1.2.4   A type of development where young birds are born with their eyes closed
              and with no feathers

      1.2.5   The structure that provides nutrients to the developing embryo in
              ovoviviparous animals
                                                                                   (5 x 1)    (5)

1.3   Indicate whether each of the statements in COLUMN I apply to A ONLY,
      B ONLY, BOTH A AND B or NONE of the items in COLUMN II. Write A only,
      B only, both A and B, or none next to the question number (1.3.1 to 1.3.3) in
      the ANSWER BOOK.

                         COLUMN I                                  COLUMN II
      1.3.1   Hormone responsible for the falling off of   A   Abscisic acid
              ripe fruit                                   B   Gibberellins
      1.3.2   Function/s of the allantois in an amniotic   A   Involved in gaseous
              egg                                              exchange
                                                           B   Stores excretory waste
                                                               from the developing
                                                               embryo
      1.3.3   A fish, laying eggs prior to fertilization   A   External fertilization
                                                           B   Ovipary
                                                                                    (3 x 2)   (6)

                                                                                              P.T.O.

### Page 7

Downloaded from hlayiso.com
                                            LIFE SCIENCES                                         7
                                            (Paper 1)                            10831/21

1.4   The diagram below represents the human male reproductive system.

                                                                             A

                                                                             B

                                                                             C
         H
                                                                             D

                                                                             E

          G                                                                  F

      1.4.1   Give the LETTER of the part that is associated with each of the
              following statements:

              (a) Temporarily stores sperm                                                  (1)

              (b) If cut, semen will not contain sperm cells                                (1)

              (c) Transports both urine and semen                                           (1)

              (d) Assists in optimum sperm production at a temperature lower than
                  body temperature                                                          (1)

              (e) Produces testosterone                                                     (1)

              (f)   Secretes alkaline fluid which neutralises the acidity of the vagina,
                    which would kill sperm                                                  (1)
                                                                                            (6)

                                                                                             P.T.O.

### Page 8

Downloaded from hlayiso.com
                                          LIFE SCIENCES                                   8
                                          (Paper 1)                         10831/21

1.5   A young seedling was removed from the soil and placed on its side. Once
      placed on its side, the shoot excluding the tip, was exposed to light from all
      directions (indicated by the arrows), to prevent phototropism.

                                F                      A
                         E                                      B
                                                       C
                                  D

                                          AFTER

      1.5.1   Name the hormone which stimulates seed germination.                      (1)

      1.5.2   Name the tropic movement that will be observed in the seedling above,
              after it was placed on its side.                                         (1)

      1.5.3   Give the LETTER/S of the area/s where:

              (a)   The seedling had the highest concentration of auxins BEFORE
                    being placed on its side                                           (2)

              (b)   The seedling would have the highest concentration of auxins
                    AFTER being placed on its side                                     (2)

              (c)   Cell elongation would be inhibited in the shoot                    (2)

      1.5.4   Name TWO defence mechanisms used by plants to stop herbivores
              from eating them.                                                         (2)
                                                                                       (10)

                                                                                        P.T.O.

### Page 9

Downloaded from hlayiso.com
                                           LIFE SCIENCES                                        9
                                           (Paper 1)                           10831/21

1.6   The diagram below shows different glands, the hormones they release and
      their target organs.

                                      A

                                                                       B
                           D

                                                                       C

                                                Kidney

      1.6.1   Identify each of the following:

              (a) The glands labelled A and B                                             (2)

              (b) The hormones labelled C and D                                           (2)

      1.6.2   Which substance in the body is regulated by hormone C?                      (1)

      1.6.3   Name ONE other hormone released by gland B.                                 (1)

      1.6.4   Give the term used to describe the regulation of a constant internal
              balance, even if the internal or external environment changes.              (1)
                                                                                          (7)

                                                                TOTAL SECTION A:          50

                                                                                           P.T.O.

### Page 10

Downloaded from hlayiso.com
                                                                              LIFE SCIENCES                                10
                                                                              (Paper 1)                       10831/21

SECTION B

QUESTION 2

2.1   The graph below shows changes in the diameter of the pupil under different
      luminances. Luminances refer to how bright the light is. The diameter of the
      pupil ranges from approximately 2 mm to 8 mm.

                                                      Diameter of the pupil at different luminances
                                           9
                                               7.7

              Diameter of the pupil (mm)
                                                         7.5
                                           8                     6.9
                                           7                             A
                                           6                                     4.9
                                           5
                                                                                       3.8
                                           4                                                  B
                                                                                                    2.5
                                           3                                                                2.1
                                           2
                                           1
                                           0
                                           0.0001       0.001    0.01   0.1       1    10     100   1000   10000
                                                                        Luminance (cd/m2)

      2.1.1       Give the diameter of the pupil at point A.                                                             (1)

      2.1.2       Calculate the average diameter of the pupil using only the points
                  indicated between A and B on the graph. (Show all working.)                                            (3)

      2.1.3       Describe the relationship between luminance and the diameter of the
                  pupil from point A to point B.                                                                         (2)

      2.1.4       Explain the role that pupillary reflex plays in changing the diameter of
                  the pupil from point A to point B.                                                                     (3)

      2.1.5       Define each of the following:

                  (a)                                Luminance                                                           (1)

                  (b)                                A reflex action                                                     (2)

      2.1.6       The beam of light from a laser pointer has a high enough luminance to
                  burn any receptor cell in the retina in about 10 seconds.

                  Explain how shining a laser pointer directly onto the retina for more
                  than 10 seconds, will affect your eyesight.                                                             (3)
                                                                                                                         (15)

                                                                                                                          P.T.O.

### Page 11

Downloaded from hlayiso.com
                                          LIFE SCIENCES                                   11
                                          (Paper 1)                          10831/21

2.2   The diagram below shows the internal structure of the eye.

                                                                   A

                                                                   B

                  Optic nerve

      2.2.1   Identify the structures labelled A and B.                                 (2)

      2.2.2   The optic nerve is a sensory neuron.
              Tabulate TWO differences between a sensory neuron and a motor
              neuron.                                                                   (5)

      2.2.3   Name the part of the nervous system which is composed of cranial and
              spinal nerves.                                                            (1)

      2.2.4   Describe how structures A and B enable the ability to focus on objects
              further than 6 m away.                                                     (4)
                                                                                        (12)

                                                                                         P.T.O.

### Page 12

Downloaded from hlayiso.com
                                            LIFE SCIENCES                                   12
                                            (Paper 1)                          10831/21

2.3   The diagram below shows a section through the human brain.

                                        Cerebrum
                                                      Corpus callosum

                                                   Pons
                    Cerebellum
                    Spinal cord
                                               Medulla oblongata

      2.3.1   Give ONE function for each of the following:

              (a)     The corpus callosum

              (b)     The cerebrum

              (c)     The spinal cord                                                     (3)

      2.3.2   Draw a labelled diagram of a simple reflex arc and indicate the direction
              in which the impulse travels.                                               (5)
                                                                                          (8)

                                                                                           P.T.O.

### Page 13

Downloaded from hlayiso.com
                                            LIFE SCIENCES                                    13
                                            (Paper 1)                           10831/21

2.4   The diagram below shows the internal structure of the ear.

                                                 A

                                                                                B

                                                                                C

                                                                                D

                              F                  E

      2.4.1   Give the LETTER and NAME of the part of the ear that:

              (a)    Allows air to move between the middle ear and the throat              (2)

              (b)    Contains receptors for hearing                                        (2)

              (c)    Is a membrane separating the outer ear from the middle ear            (2)

              (d)    Is the first of three ossicles                                        (2)

              (e)    Conducts sound waves from the pinna to the structure labelled E       (2)

      2.4.2   In a soccer match the goalkeeper dived to save a goal from being
              scored by the opposing team.

              Describe the role of the semi-circular canals in maintaining balance as
              the goalkeeper dived.                                                         (5)
                                                                                           (15)

                                                                                           [50]

                                                                                            P.T.O.

### Page 14

Downloaded from hlayiso.com
                                          LIFE SCIENCES                                      14
                                          (Paper 1)                             10831/21

QUESTION 3

3.1   Read the extract below and answer the questions that follow.

      The Comrades Marathon is an ultra-marathon of approximately 89 kilometres
      which is run annually in the KwaZulu-Natal province between the cities of
      Durban and Pietermaritzburg. It is the world’s largest and oldest ultra-
      marathon race. Athletes run up to 12 hours continually to complete the race.
      Runners train for many months and they carbo-load (consume a diet high in
      carbohydrates such as pastas and grains) in preparation for this race.

      3.1.1   While running, an athlete’s body temperature increases.

              Describe the negative feedback mechanism that will restore the
              athlete’s body temperature to normal.                                        (6)

      3.1.2   Explain the effect of running for long periods of time on each of the
              following:

              (a)    Water levels in the blood                                             (2)
              (b)    Carbon dioxide levels in the blood                                    (2)

      3.1.3   Explain how carbo-loading before the race assists athletes to have
              enough energy during the race.                                                (6)
                                                                                           (16)

                                                                                            P.T.O.

### Page 15

Downloaded from hlayiso.com
                                             LIFE SCIENCES                                   15
                                             (Paper 1)                          10831/21

3.2   Read the extract below and answer the questions that follow.

      Tshepang read a WhatsApp message which stated: “Wearing a facemask
      increases the carbon dioxide levels in the blood and could lead to sickness.”
      He decided to conduct an investigation to determine whether wearing a
      facemask increases the carbon dioxide levels in the blood.

             He could not afford a device that measures the carbon dioxide levels in
              the blood, so he decided to measure the pulse rate (indicates heart rate)
              and the breathing rate.
             He chose 10 classmates for the investigation.
             The breathing rate and pulse rate of each classmate was measured,
              after 4 hours of not wearing a facemask and again after 4 hours of
              wearing a facemask.

      3.2.1     Identify the dependent variable in this investigation.                     (1)

      3.2.2     State TWO variables which relate to the classmates and should be kept
                constant in order to ensure the validity of this investigation.            (2)

      3.2.3     Give TWO planning steps that Tshepang needed to consider before
                conducting his investigation.                                              (2)

      3.2.4     Explain how the breathing rate can be used to show an increase in the
                carbon dioxide levels in the blood.                                        (4)
                                                                                           (9)

                                                                                            P.T.O.

### Page 16

Downloaded from hlayiso.com
                                           LIFE SCIENCES                                      16
                                           (Paper 1)                             10831/21

3.3   Read the extract below and answer the questions that follow.

                       How to optimise the chances of conception

      It is estimated that one in five couples in South Africa are suffering from
      infertility and are experiencing difficulty in conceiving. Research has shown that
      conception (fertilization) is more likely to happen when intercourse takes place
      in the 3 or 4 days leading up to ovulation. Recent evidence has also shown that
      many women have a poor understanding of their menstrual cycle and the
      process of ovulation. Incorrect timing of intercourse is therefore thought to be a
      common, but easily correctable cause of difficulty in conceiving.

      The introduction of home-based hormonal digital ovulation tests (DOTs) has at
      least provided a simple solution for women wishing to optimise the timing of
      intercourse when trying to conceive.

      3.3.1   Give TWO reasons according to the passage, why women may have
              difficulty conceiving.                                                        (2)

      3.3.2   The digital ovulation test monitors an increase in a specific hormone.
              Name this hormone.                                                            (1)

      3.3.3   Name the gland that produces the hormone mentioned in
              QUESTION 3.3.2.                                                               (1)

      3.3.4   Name the gland that releases a hormone which triggers ovulation.              (1)

      3.3.5   Give ONE reason why intercourse should take place 3 to 4 days before
              ovulation.                                                                    (1)

      3.3.6   Explain why the secretion of too little progesterone can pose an
              additional problem to a female trying to fall pregnant.                       (2)
                                                                                            (8)

                                                                                             P.T.O.

### Page 17

Downloaded from hlayiso.com
                                           LIFE SCIENCES                                      17
                                           (Paper 1)                             10831/21

3.4   An ultrasound (sonogram) is an imaging technique that uses sound waves to
      produce images of the foetus in the uterus. Dr Mkhize monitored the
      development of the foetus in one of her patients during pregnancy by
      measuring the foetal head circumference. She also monitored the blood flow
      along the umbilical cord.

      The results are shown in the table below.

                        Time (weeks)              Head circumference (cm)
                              14                             12
                              18                             16
                              22                             20
                              26                             24
                              30                             28
                              34                             31
                              38                             33
                              40                             36

      3.4.1   Give the correct biological term for pregnancy.                               (1)

      3.4.2   Use the information in the table above to plot a line graph.                  (6)

      3.4.3   Give THREE functions of the amniotic fluid that surrounds the foetus
              during pregnancy.                                                             (3)

      3.4.4   List TWO structures through which the foetus will pass during natural
              birth.                                                                        (2)

      3.4.5   While doing the ultrasound, the doctor noticed that the umbilical
              arteries were blocked but there was normal blood flow through the
              umbilical vein.

              Explain the effect that this will have on the developing foetus.               (5)
                                                                                            (17)

                                                                                            [50]

                                                                  TOTAL SECTION B:          100

                                                                                 TOTAL:     150

                                              END

## Related documents

- [Gr12 Life Sciences P2 (English) 2021 Preparatory Question Paper](https://www.hlayiso.com/library/gr12-life-sciences-p2-english-2021-preparatory-question-paper/3f3721a2-ca17-4caa-900e-7c73d1b99db8) — Life Sciences · QP · 2021 · Eng
- [LIFE SCIENCES P1 QP GR12 SEPT2021 English](https://www.hlayiso.com/library/life-sciences-p1-qp-gr12-sept2021-english/51bdf0cb-548d-43fc-b083-c4f0f664b370) — Life Sciences · QP · 2021 · Eng
- [Grade 12 NSC Life Sciences P2 (English) X10 2019 Preparatory Examination Question Paper](https://www.hlayiso.com/library/grade-12-nsc-life-sciences-p2-english-x10-2019-preparatory-examination-question-paper/4abde6f1-8134-4898-b5d2-7a1108fd269d) — Life Sciences · QP · 2019 · Eng
- [Gr 12 Life Sciences P1 (English) June 2024 Question Paper](https://www.hlayiso.com/library/gr-12-life-sciences-p1-english-june-2024-question-paper/4fc6ccbd-0c7e-4401-885a-2cf93f82dfd5) — Life Sciences · QP · 2024 · Eng
- [LIFE SCIENCES P1 QP SEPT2019 English final](https://www.hlayiso.com/library/life-sciences-p1-qp-sept2019-english-final/0aee37ba-cb6c-4703-8a28-3bd5d8231c5d) — Life Sciences · QP · 2019 · Eng
- [LIFE SCIENCES P1 QP SEPT 2021 Xhosa D](https://www.hlayiso.com/library/life-sciences-p1-qp-sept-2021-xhosa-d/bf73c123-831d-499a-9ecd-62ac37eff2bf) — Life Sciences · QP · 2021

## More from Grade 12 Life Sciences

- [LEWENSWETENSKAPPE V1 MEMO GR12 SEPT 2025 watermark](https://www.hlayiso.com/library/lewenswetenskappe-v1-memo-gr12-sept-2025-watermark/ee8ac4d1-8b43-4b2a-87fc-d07277b88025) — Memo · 2025
- [LIFE SCIENCES P2 MEMO GR12 SEPT 2025 AFR watermark](https://www.hlayiso.com/library/life-sciences-p2-memo-gr12-sept-2025-afr-watermark/be114f07-9b13-48d1-9cae-e0ae8aec035b) — Memo · 2025 · Afr
- [Life Sciences Grade 12 NSC P1 MEMO September 2025 Free State](https://www.hlayiso.com/library/life-sciences-grade-12-nsc-p1-memo-september-2025-free-state/ba194139-8ff7-481e-92f4-d961a5c8d23a) — Memo · 2025
- [Life Sciences Grade 12 NSC P2 MEMO September 2025 Free State](https://www.hlayiso.com/library/life-sciences-grade-12-nsc-p2-memo-september-2025-free-state/470ae841-15a4-4ab3-a87b-abd2294edc20) — Memo · 2025
- [Life Sciences Grade 12 NSC P2 MEMO September 2025 Gauteng](https://www.hlayiso.com/library/life-sciences-grade-12-nsc-p2-memo-september-2025-gauteng/bbdf9d27-c483-4cd4-af9f-287e699f482e) — Memo · 2025
- [Life Sciences Grade 12 NSC P2 MEMO September 2025 KZN](https://www.hlayiso.com/library/life-sciences-grade-12-nsc-p2-memo-september-2025-kzn/f412416e-57d1-473d-886a-87c9fbb8823c) — Memo · 2025

## Collection

- [Grade 12 past papers](https://www.hlayiso.com/grade-12/past-papers)

---

Hlayiso: free CAPS and IEB past papers, memos, notes and study guides for South African learners. When citing, link the page URL above, not a PDF or /api/ URL.
