Life Sciences Grade 12 Paper 1 Eastern Cape Mock 2025 Memo

NATIONAL SENIOR CERTIFICATE GRADE 12 SEPTEMBER 2025 LIFE SCIENCES P1 MARKING GUIDELINE MARKS: 150 This marking guideline consists of 11 pages.

2 LIFE SCIENCES P2 (EC/SEPTEMBER 2025) PRINCIPLES RELATED TO MARKING LIFE SCIENCES 1. If more information than marks allocated is given Stop marking when maximum marks is reached and put a wavy line and ‘max’ in the right-hand margin. 2. If, for example, three reasons are required and five are given Mark the first three irrespective of whether all or some are correct/incorrect. 3. If whole process is given when only a part of it is required Read all and credit the relevant part. 4. If comparisons are asked for but descriptions are given Accept if the differences/similarities are clear. 5. If tabulation is required but paragraphs are given Candidates will lose marks for not tabulating. 6. If diagrams are given with annotations when descriptions are required Candidates will lose marks. 7. If flow charts are given instead of descriptions Candidates will lose marks. 8. If sequence is muddled and links do not make sense Where sequence and links are correct, credit. Where sequence and links are incorrect, do not credit. If sequence and links become correct again, resume credit. 9. Non-recognised abbreviations Accept if first defined in answer. If not defined, do not credit the unrecognised abbreviation but credit the rest of the answer if correct. 10. Wrong numbering If answer fits into the correct sequence of questions but the wrong number is given, it is acceptable. 11. If language used changes the intended meaning Do not accept. 12. Spelling errors If recognisable, accept the answer, provided it does not mean something else in Life Sciences or if it is out of context. 13. If common names are given in terminology Accept, provided it was accepted at the provincial memo discussion meeting. Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 3 14. If only the letter is asked for but only the name is given (and vice versa) Do not credit. 15. If units are not given in measurements Candidates will lose marks. Marking guideline will allocate marks for units separately. 16. Be sensitive to the sense of an answer, which may be stated in a different way. 17. Caption All illustrations (diagrams, graphs, tables, etc.) must have a caption. 18. Code-switching of official languages (terms and concepts) A single word or two that appear(s) in any official language other than the learners' assessment language used to the greatest extent in his/her answers should be credited if it is correct. A marker that is proficient in the relevant official language should be consulted. This is applicable to all official languages. Copyright reserved Please turn over

4 LIFE SCIENCES P2 (EC/SEPTEMBER 2025) SECTION A QUESTION 1 1.1.1 B  1.1.2 A  1.1.3 B  1.1.4 D  1.1.5 C  1.1.6 C  1.1.7 B  1.1.8 D  1.1.9 A  1.1.10 B  (10 x 2) (20) 1.2.1 Puberty  1.2.2 Thorns  1.2.3 (Reproductive) strategy  1.2.4 Binocular vision  1.2.5 Testes  1.2.6 Kidney  1.2.7 Stimulus  1.2.8 Chorion  1.2.9 Multiple Sclerosis  (9 x 1) (9) 1.3.1 Both A and B  1.3.2 Both A and B  1.3.3 None  (3 x 2) (6) 1.4.1 (a) A  – Prostate gland  (2) (b) B  – Epididymis  (2) 1.4.2 - Penis/D deposits sperm directly into the female reproductive tract  during ejaculation, - ensuring that sperm are closer to the egg cell  for potential fertilisation. (Mark first ONE only) (1 x 2) (2) 1.5.1 (a) Oviparous  (1) (b) Allantois  (1) 1.5.2 - The foetus obtains nutrients directly from the mothers’ body  - The foetus is protected by the mother’s body from the environment  (Mark first TWO only) (2) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 5 1.6.1 (a) TSH/Thyroid stimulating hormone  (1) (b) Thyroid gland  (1) (c) Negative feedback  mechanism (1) 1.6.2 (a) Goitre  (1) (b) Thyroxin  (1) [50] TOTAL SECTION A: 50 Copyright reserved Please turn over

6 LIFE SCIENCES P2 (EC/SEPTEMBER 2025) SECTION B QUESTION 2 2.1 2.1.1 (a) A – Pinna  (1) (b) D – Auditory nerve  (1) 2.1.2 - The buildup of fluid in the middle ear increases pressure which reduces the ability of the tympanic membrane (structure E) to vibrate effectively  As a result, fewer sound vibrations are transmitted to the ossicles (structure B)  - The fluid also restricts the movement of the ossicles, reducing the ability to amplify sound  This leads to less mechanical vibrations being passed on to the inner ear resulting in the hearing loss. (4) 2.1.3 - Insert grommet (into structure E) (1) 2.1.4 - The use of earplugs to prevent water entry to the middle ear  (1) 2.1.5 The semi-circular canals / structure C: - Are arranged at (right) angles of each other  To detect movement in three different planes/ as endolymph is displaced in each receptor(s) are stimulated  - Contain cristae and ampullae  Detecting the speed of change in rotational movement of the head  - Contain endolymph  That is displaced with head movement/rotation causing the cupula to bend  (Mark first TWO only) (2 x 2) (4) 2.2 2.2.1 Accommodation  (1) 2.2.2 - Ciliary muscle relax  - Suspensory ligaments are pulled taught  - Tension on lens increases  - Making the lens become flatter/less convex  Light rays are refracted (bent) less  (Any 4 x 1) (4) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 7 2.2.3 Marking guideline for drawing Correct lens shape (concave) - S 1 Mark Incoming light rays - L 1 Mark How the light rays are adjusted (bended) to focus correctly on the retina - B 1 Mark (3) 2.3 2.3.1 - The path an impulse takes  from - receptor to effector  (2) 2.3.2 - Transmits impulses  from receptors to the brain  - Transmits impulses  from the brain to effectors  - It helps coordinate muscle movements and balance  by transmitting impulses between the brain and body.  (Mark first ONE only) (Max 2) (Any 1 x 2) (2) 2.3.3 B/ Sensory neuron D/ Motor neuron Unipolar  Multipolar  Enter the spinal Exit spinal cord via cord via the dorsal ventral root  root  (Mark first TWO only) Table + (2 x 2) (5) 2.3.4 Synapse * - It ensures that the impulse moves in one direction only  - It prevents continuous stimulation of the neurons  - It ensures that the impulse is transmitted from the sensory neuron to the motor neuron (Mark first TWO only and *) (3) Copyright reserved Please turn over

8 LIFE SCIENCES P2 (EC/SEPTEMBER 2025) 2.4 2.4.1 Autonomic nervous system  (1) 2.4.2 - Sympathetic nerve Increase cardiac rhythm  increasing blood flow around the body - Parasympathetic Returning  cardiac rhythm back to normal  operating conditions (4) 2.5 2.5.1 Aldosterone  (1) 2.5.2 83  x 2 600  = 599,44  cm3 360 (3) 2.5.3 - ADH will travel in the blood to the kidneys/nephron  - Causing an increase in permeability  - Within the collecting ducts/nephron  - More water is absorbed from the filtrate  - Less water is expelled through the urine  (Any 4 x 1) (4) 2.5.4 (a) Cold day  (1) (b) - High volume of urine produced * During a cold day, the body sweats less and produces more, urine to remove extra water  - Little sweat is being produced * During a cold day, the body does not need to cool down, so less sweat is produced  (Mark FIRST TWO only) (2 x 2) (4) [50] Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 9 QUESTION 3 3.1 3.1.1 (a) Implantation  (1) (b) Morula  (1) 3.1.2 - Facilitate the movement of sperm cells, egg cells and the zygote to the uterus/produce peristaltic movements to facilitate movements of sperm, egg and zygote/ to catch and usher ovum into Fallopian tube - Site of fertilisation  - To keep sperm cells, egg cells and the zygote hydrated / provides a suitable environment/nourishment for the fertilized ovum (zygote) before it moves to the uterus. (Any 2) OR - Helps sperm reach the ovum  for fertilisation  - To keep sperm cells, egg cells and the zygote hydrated / provides a suitable environment/nourishment for the fertilized ovum (zygote) before it moves to the uterus. (Any 2) (2) 3.1.3 - The hormones, estrogen and progesterone * cause the endometrium to become - more vascular  - more glandular increasing the endometrium lining size – more glandular  (Mark * + Any 1 only) (2) 3.1.4 - Nutrition  It allows for diffusion of nutrients from the mother to the foetus  - Gaseous exchange  Diffusion of oxygen from the mother to the foetus and for the diffusion of carbon dioxide from the foetus to the mother  - diffusion of waste products and nutrients  from the foetus to the mother  - Endocrine function  After 12 weeks, the placenta secretes progesterone to maintain the pregnancy  - Acts as a microfilter  Preventing pathogenic microbes and certain toxins from entering into foetal blood. (Mark first THREE only) (3 x 2) (6) Copyright reserved Please turn over

10 LIFE SCIENCES P2 (EC/SEPTEMBER 2025) 3.1.5 - Limited nutrition,  the developing foetus will not be able to receive enough nutrients and oxygen  - Toxicity  might build up in the foetus as there will be limited removal of metabolic waste products  (Mark first TWO only) (2 x 2) (4) 3.2 3.2.1 Pituitary/hypophysis  gland (1) 3.2.2 Clomiphene treatment  (1) 3.2.3 - Day 10/11  (1) 3.2.4 - FSH cause the development of mature Graafian follicle.  - As a Graafian follicle grows, it secretes more oestrogen.  - Therefore, rising oestrogen levels indicate that FSH is active and functioning.  (2) 3.2.5 - Acquiring research tools/instruments  to collect data with - Deciding on how data will be recorded  (2) 3.2.6 - Allowing researchers to identify trends  - Reduces effects of random errors  /outliers - Improves accuracy of results  (Any TWO) (2) 3.2.7 (a) The release of a (mature) ovum  from the ovary/mature Graafian follicle  (2) (b) - Oestrogen levels peaked/drastically increased twice,  - Once at day 10 and the other at day 20  - Oestrogen is secreted from developing follicles  and - the greater the size of the Graafian follicle, the greater amount of oestrogen secreted  - Oestrogen levels usually spike the day before ovulation, it spiked twice within 27 days.  (Any FOUR) (4) 3.3 3.3.1 - Decreased water availability/drought  - Parasitism  - Decreased light intensity  - Coldness  - Increased transpiration  (Any ONE) (1) 3.3.2 - Inhibits plant growth in unfavourable conditions  - Preventing the plant from expending energy where it might not be able to photosynthesise efficiently.  (2) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 11 3.3.3 Spring / Summer  (1) 3.3.4 - Higher UV radiation will be available, plants will be able to photosynthesise better  - GA stimulates cell elongation/plant growth/flowering to harness increased environmental energy  (2) 3.4 In seedling A - Auxins produced in the apical meristem - Could not detect light direction  - And remained evenly distributed  - Causing the seedling to grow upwards  (Any TWO) (2) In seedling C - Auxins produced in the apical meristem - Where unevenly distributed  - Accumulating on the left-hand side, causing cell elongation  - Causing the seedling to bend towards the right  (Any TWO) (2) 3.5 3.5.1 When insulin doesn’t work properly, brain cells struggle to communicate, leading to memory problems.  (2) 3.5.2 - amyloid plaques  - tau tangles  (2) 3.5.3 - Insulin will stimulate liver / hepatic / muscle cells  - To convert excess glucose to glycogen  which is stored in them (2) 3.5.4 - Insulin Resistance  OR - The body being unable to convert glucose to glycogen  despite the secretion of insulin into the blood (1) 3.5.5 - Adrenalin  - Could cause an increase in cellular respiration within cells, thus uptake of glucose  (2) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright reserved Please turn over