Life Sciences Grade 12 P1 Eastern Cape Mock 2025 QP (Eng)

NATIONAL SENIOR CERTIFICATE GRADE 12 SEPTEMBER 2025 LIFE SCIENCES P1 MARKS: 150 TIME: 2½ hours This question paper consists of 18 pages.

2 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) INSTRUCTIONS AND INFORMATION Read the following instructions carefully before answering the questions. 1. Answer ALL the questions. 2. Write ALL the answers in the ANSWER BOOK. 3. Start the answer to EACH question at the top of 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. ALL drawings MUST be done in pencil and labelled in blue or black ink. 7. Draw diagrams, tables or flow charts 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 must use a non-programmable calculator, protractor and a compass where necessary. 11. All calculations to be rounded off to TWO decimal places. 12. Write neatly and legibly. Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 3 SECTION A QUESTION 1 1.1 Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A–D) next to the question numbers (1.1.1 to 1.1.10) in the ANSWER BOOK, for example 1.1.11 D. 1.1.1 A key function of the scrotum: A Produces the male sex hormone, testosterone B Regulates the temperature of the testes C Stores mature spermatozoa D Transports spermatozoa to the urethra 1.1.2 An eye condition where the cornea and/or lens is not perfectly rounded, causing light not to be properly focused on the retina. A Astigmatism B Short sightedness C Long sightedness D Cataract 1.1.3 The part of the brain that functions as the control center for hunger, thirst, sleep, and body temperature regulation is the … A cerebellum. B hypothalamus. C cerebrum. D medulla oblongata. 1.1.4 Which of the coleoptiles displayed below demonstrates negative geotropism after 48 hours? A B C D Light Light Gravity Gravity Copyright reserved Please turn over

4 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 1.1.5 The following is a list of target effectors. (i) Pancreas (ii) Muscles (iii) Testes (iv) Liver Which of the structures listed above are directly targeted by human growth hormone to stimulate growth and metabolism? A (iii) only B (i) and (iii) only C (ii) and (iv) only D (ii) only 1.1.6 The diagram below represent the pupillary mechanism in the human eye. X Z Y A person suddenly looks up from their bright mobile phone screen to a dark room. What structural changes occur in X, Y and Z respectively? X Y Z A Contract Relax Constrict B Relax Contract Dilate C Contract Relax Dilate D Relax Contract Constrict Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 5 1.1.7 The illustration below represents a 28-day menstrual cycle. Menstruation Menstruation X Y Z Day Day Day Day 0 14 21 28 Based on the above illustration, select the correct option of different hormonal levels. Hormone X Hormone Y Hormone Z Progesterone A LH is high Oestrogen decreases increases Progesterone B FSH increases LH is low decreases Progesterone C LH is low Oestrogen increases decreases Progesterone D FSH increases LH is high increases 1.1.8 Which ONE the following diagrams best suit the homeostatic processes of the skin when the median temperature drops below 0 oC? A B C D 1.1.9 The part of the eye that prevents internal reflection of light. A Choroid B Sclera C Cornea D Aqueous humor Copyright reserved Please turn over

6 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 1.1.10 A man injures his arm in an accident. Afterwards, he can feel objects touching his hand, but he cannot move his hand away from them. What is most likely to have caused this? A Receptors in his hand are damaged. B The nerve connection is cut only between his central nervous system and the effectors in his arm. C The nerve connection is cut only between the receptors in his hand and his central nervous system. D Both nerve connections, to and from the central nervous system are cut off. (10 x 2) (20) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 7 1.2 Give the correct biological term for each of the following descriptions. Write only the term next to the question numbers (1.2.1 to 1.2.9) in the ANSWER BOOK. 1.2.1 Period when males and females reach sexual maturity 1.2.2 A mechanical defence mechanism employed by plants to deter herbivory 1.2.3 Reproductive methods used by organisms to maximise their reproductive success 1.2.4 The use of two eyes with overlapping fields of view so that separate images are combined and interpreted 1.2.5 The two oval-shaped organs located in the male reproductive system which produce the male hormone testosterone 1.2.6 The target organ for the hormone aldosterone responsible for salt regulation 1.2.7 Detectable changes that have occurred in the internal and/or external environment to which a response is generated 1.2.8 Membrane in the amniotic egg that allows for gaseous exchange and, forms the placenta in mammals 1.2.9 An autoimmune disease characterised by the degradation of myelin sheath and the slowing down of nerve impulses (9 x 1) (9) 1.3 Indicate whether each of the descriptions in COLUMN Ι, applies to A ONLY, B ONLY, BOTH A and B, or NONE of the items in COLUMN ΙΙ. Write A only, B only, both A and B, or NONE next to the question numbers (1.3.1–1.3.3) in the ANSWER BOOK. COLUMN I COLUMN II 1.3.1 Components of a negative feedback A: Control centre system B: Effector 1.3.2 Secretory products released into a duct, A: Endocrine gland not the blood B: Exocrine gland 1.3.3 Components of the central nervous A: Cranial nerves system B: Spinal nerves (3 x 2) (6) Copyright reserved Please turn over

8 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 1.4 The diagram below represents the side view of the human male reproductive system. E A D B C 1.4.1 Give the LETTER and NAME of the structure that: (a) Produces an alkaline fluid that neutralisers the vagina’s acidity (2) (b) Stores mature spermatozoa (2) 1.4.2 Explain ONE way how structure D increases the chances of internal fertilisation. (2) 1.5 1.5.1 Name the: (a) Reproductive strategies in which eggs are produced (1) (b) Extra embryonic membrane that collects nitrogenous waste and assists in the exchange of gases (1) 1.5.2 List TWO benefits of vivipary that increase foetus survival. (2) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 9 1.6 The diagram below represents the interaction between two important endocrine glands. A B 1.6.1 Identify the: (a) Hormone secreted by A (1) (b) Gland represented by B (1) (c) Type of interaction represented by the diagram (1) 1.6.2 Name the: (a) Disorder that is characterised by the enlargement of gland B (1) (b) Hormone that stimulates the body to increase the metabolic rate when required (1) [50] TOTAL SECTION A: 50 Copyright reserved Please turn over

10 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) SECTION B QUESTION 2 2.1 Glue ear, also known as ‘otitis media with effusion,’ is a condition where fluid builds up in the middle-ear. The diagram below displays this condition. A B C D E Fluid Build-up 2.1.1 Identify part: (a) A (1) (b) D (1) 2.1.2 Describe how glue ear will inhibit the functioning of structures E and B. (4) 2.1.3 State a suitable treatment to drain fluid build-up. (1) 2.1.4 Identify ONE precaution to prevent fluid build-up when swimming with the treatment mentioned in QUESTION 2.1.3. (1) 2.1.5 Explain TWO ways structure C is adapted for its function. (4) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 11 2.2 The table below shows the distance of an object from the eye and the approximate lens thickness (mm). DISTANCE OF OBJECT FROM EYE (m) LENS THICKNESS (mm) 20 3,5 17 3,7 12 3,8 6 4,0 2 4,3 1 4,5 0,4 5,2 2.2.1 Name the process that occurs in the eye when an object is closer than six meters. (1) 2.2.2 Describe the changes in the eye that allow a clear image to form on the retina when an object is 17 meters away. (4) 2.2.3 If the lens is fixed and unable to change its curvature due to near- sightedness. Draw a diagram of the spectacle lens needed to correct this for seeing distant objects. Include the path of incoming light rays and how they are adjusted to focus correctly on the retina. (3) Copyright reserved Please turn over

12 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 2.3 The diagram below shows a reflex arc. 2.3.1 Define the term reflex arc. (2) 2.3.2 Apart from being the reflex centre, describe ONE additional function of part E. (2) 2.3.3 Tabulate TWO visible structural differences between neurons B and D. (5) 2.3.4 Identify the structure formed at part A and state TWO of its significances. (3) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 13 2.4 Most effector organs of the human body are double innervated, meaning they receive connections from both sympathetic and parasympathetic nerve fibres. 2.4.1 To which division of the nervous system do the above nerve fibres belong? (1) 2.4.2 Discuss ONE reason, for each type of nerve fibre, as to why the heart requires double innervation. (4) 2.5 The pie chart below displays the collective amount of water lost by an individual over a 24-hour period. The total amount of water lost was 2 600 cm3. Faeces 18° Exhaled air 61° Urine198° Sweat 83° 2.5.1 Name the hormone secreted from the adrenal glands, that helps regulate water balance. (1) 2.5.2 Determine the amount of water, in cm3, lost through sweat. (3) 2.5.3 Explain how ADH assists to conserve water. (4) 2.5.4 From your observations of the above graph: (a) Is the individual experiencing a hot or cold day? (1) (b) Describe TWO reasons for the answer to QUESTION 2.5.4(a). (4) [50] Copyright reserved Please turn over

14 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) QUESTION 3 3.1 The diagram below is a female reproductive system showing development of zygote to foetus. G F E A D C B 3.1.1 Provide labels for: (a) Process D (1) (b) Structure F (1) 3.1.2 Name TWO functions of structure G. (2) 3.1.3 Explain how ovarian hormones cause structure A to thicken. (2) 3.1.4 Describe THREE functions of structure B. (6) 3.1.5 If too few of structure C forms, discuss TWO ways this will negatively affect the growth of the foetus. (4) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 15 3.2 Clomiphene is a medication used to treat infertility in women. Researchers wanted to find out how well Clomiphene helps to improve fertility. Clomiphene increases FSH levels, which helps ova grow and be released, improving the chances of pregnancy. A woman taking clomiphene for infertility was treated for five days. Her blood oestrogen levels were measured every day for 27 days. The research followed these guidelines: • The woman had to have low FSH levels, too low for normal ovum production. • She had to be healthy, without any diseases, and between 18 and 40 years old. • She could not have a family history of infertility. • She took 50 g of Clomiphene by mouth each day for 5 days. • She had to give consent for the study and agree that the researchers would not be responsible for multiple pregnancies. CONCENTRATION OF OESTROGEN IN A FEMALEʼS BLOOD OVER 27 DAYS 170 Concentration of oestrogen in the blood in 160 150 140 130 120 110 100 90 80 arbitrary units 70 60 50 40 30 20 10 0 0 3 6 9 12 15 18 21 24 27 Medication intake Day 3.2.1 Name the endocrine gland responsible for FSH secretion. (1) 3.2.2 Identify the independent variable of this investigation. (1) 3.2.3 According to the graph, on which day was the female most fertile? (1) Copyright reserved Please turn over

16 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 3.2.4 Explain why researchers used oestrogen levels in the blood to monitor FSH availability in the blood. (2) 3.2.5 Apart from the information stated in the research parameters, list TWO additional planning steps researchers would have needed to consider. (2) 3.2.6 How does repeating the investigation with 25 more women make the results more reliable? (2) 3.2.7 Fertility doctors believe that two ovulation events occurred. (a) Define ovulation. (2) (b) Discuss why two ovulation events may have occurred. (4) 3.3 Plants regulate their growth and survival through hormones like abscisic acid (ABA) and gibberellins (GA). ABA helps plants respond to stress and enter dormancy, while GA promotes growth. 3.3.1 Name ONE stress response in plants that will result in high ABA levels inducing plant dormancy. (1) 3.3.2 Explain the significance of ABA in a plant during winter. (2) 3.3.3 During which season of the year will GA be the highest? (1) 3.3.4 Describe ONE reason for your answer in QUESTION 3.3.3. (2) Copyright reserved Please turn over

(EC/SEPTEMBER 2025) LIFE SCIENCES P1 17 3.4 Researchers investigated how seedlings respond to light by covering different parts of the plant. • Seedling A had a tinfoil covering on its apical meristem • Seedling B had an opaque (semi-transparent) covering on its apical meristem • Seedling C had a tinfoil covering on its lower stem SUN A B C Describe the reason for the differences in plant growths in seedlings A and C with references to your observations to the images above. (4) 3.5 Read the extract below. LINKAGE BETWEEN DIABETES AND ALZHEIMER’S DISEASE Diabetes and Alzheimer’s disease are connected because insulin resistance affects brain function. When insulin doesn’t work properly, brain cells struggle to communicate, leading to memory problems. This is why Alzheimer’s is sometimes called Type 3 diabetes. High blood sugar causes inflammation, damages brain cells, and increases harmful proteins called amyloid plaques and tau tangles, which interfere with brain function. Diabetes also damages blood vessels, reducing oxygen and nutrient supply to the brain. Additionally, excess sugar leads to the production of Advanced Glycation End Products (AGEs), which make plaques and tangles worse. It also increases harmful molecules (Reactive Oxygen Species or ROS), damaging energy production in brain cells. 3.5.1 According to the extract, define Type 3-diabetes. (2) 3.5.2 Name TWO Alzheimer proteins that build-up in the brain disrupting its function. (2) Copyright reserved Please turn over

18 LIFE SCIENCES P1 (EC/SEPTEMBER 2025) 3.5.3 Under normal conditions state the function of insulin in a healthy individual when blood glucose rises above normal. (2) 3.5.4 What would cause glucose levels to remain high? (1) 3.5.5 Describe ONE non-thyroid endocrine hormone that could facilitate in glucose metabolism. (2) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright reserved Please turn over