Life Sciences Grade 12 P1 NSC November Prediction 2026 QP

Copyright reserved Please turn over Prediction hlayiso mock exams Practice Series: Grade 12 NSC Preparation WWW.HLAYISO.COM NATIONAL SENIOR CERTIFICATE GRADE 12 LIFE SCIENCES P1 PREDICTION EXAMINATION 2026 MARKS: 150 TIME: 2½ hours This question paper consists of 17 pages.

Life Sciences/P1 2 NSC Prediction Hlayiso/Prediction 2026 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 answers 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. Do ALL drawings in pencil and label them 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. Write neatly and legibly. Copyright reserved Please turn over

Life Sciences/P1 3 NSC Prediction Hlayiso/Prediction 2026 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 to D) next to the question numbers (1.1.1 to 1.1.10) in the ANSWER BOOK, e.g. 1.1.11 D. 1.1.1 The extra-embryonic membrane in an amniotic egg that encloses the embryo in a fluid-filled sac, which prevents the embryo from drying out, is the … A chorion. B amnion. C allantois. D yolk sac. 1.1.2 Which ONE of the following shows the CORRECT route followed by sperm cells from where they are produced to the outside of the body? A Seminiferous tubules →vas deferens →epididymis → urethra B Epididymis →seminiferous tubules →vas deferens → urethra C Seminiferous tubules →epididymis →vas deferens → urethra D Seminiferous tubules →epididymis →urethra →vas deferens 1.1.3 Which ONE of the following is CORRECT for a woman on day 7 of a normal 28-day menstrual cycle? STRUCTURE PRESENT IN THE OVARY MAIN HORMONE SECRETED BY THE OVARY ENDOMETRIUM A Corpus luteum Progesterone Thickening B Developing Graafian follicle Progesterone Breaking down C Corpus luteum Oestrogen Breaking down D Developing Graafian follicle Oestrogen Thickening 1.1.4 Both Fallopian tubes of a woman are completely blocked by scar tissue after an infection. Which ONE of the following will NOT take place in this woman? A Ovulation B Menstruation C Fertilisation D Secretion of oestrogen Copyright reserved Please turn over

Life Sciences/P1 4 NSC Prediction Hlayiso/Prediction 2026 1.1.5 Multiple sclerosis (MS) is a disorder in which the myelin sheaths around the axons of neurons are damaged. Which ONE of the following is a direct result of this damage? A Impulses are transmitted more slowly along the axons. B Impulses travel in both directions along the axons. C The cell bodies of the neurons are destroyed. D More neurotransmitter is released at the synapses. 1.1.6 A learner watching a rugby match on a distant field looks down to read the score card in her hand. Which ONE of the following describes the changes in her eyes? CILIARY MUSCLES SUSPENSORY LIGAMENTS LENS A Relax Become taut Less convex B Contract Become slack More convex C Contract Become taut More convex D Relax Become slack Less convex 1.1.7 The receptors in the ear that are stimulated when a learner spins around quickly on a merry-go-round are the … A maculae. B organ of Corti. C cristae. D ossicles. 1.1.8 A person ate a meal with a very high salt content. Which ONE of the following combinations will occur in the body of this person? SECRETION OF ALDOSTERONE REABSORPTION OF SODIUM IONS IN THE RENAL TUBULES A Increases Increases B Increases Decreases C Decreases Increases D Decreases Decreases 1.1.9 Which ONE of the following takes place in the skin of a person on a very cold day? ARTERIOLES IN THE SKIN SWEAT GLANDS A Vasoconstriction Less active B Vasodilation Less active C Vasoconstriction More active D Vasodilation More active Copyright reserved Please turn over

Life Sciences/P1 5 NSC Prediction Hlayiso/Prediction 2026 1.1.10 The graph below shows the effect of different concentrations of auxins on the growth of the roots and the stems of a plant. 10−12 10−10 10−8 10−6 10−4 10−2 -100 -50 0 50 100 Concentration of auxins (mol/dm3) Effect on growth (%) stimulation (+) / inhibition (−) Effect of auxin concentration on the growth of roots and stems Roots Stems At which concentration of auxins is the growth of the stems stimulated while the growth of the roots is inhibited? A 10−10 mol/dm3 B 10−8 mol/dm3 C 10−5 mol/dm3 D 10−2 mol/dm3 (10 x 2) (20) 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 1.2.8) in the ANSWER BOOK. 1.2.1 The finger-like projections of the chorion that grow into the endometrium to form part of the placenta 1.2.2 The production of sperm cells by meiosis in the testes 1.2.3 The ability of the lens to change its shape in order to focus on near and distant objects 1.2.4 The hormone that prepares the body to cope with an emergency (fight-or-flight) situation 1.2.5 The membrane between the middle ear and the inner ear that transmits vibrations from the stirrup into the cochlea 1.2.6 The band of nerve fibres that connects the left and the right cerebral hemispheres 1.2.7 Groups of cells in the pancreas that secrete insulin and glucagon 1.2.8 The growth movement of a plant stem towards light that comes from one direction (8 x 1) (8) Copyright reserved Please turn over

Life Sciences/P1 6 NSC Prediction Hlayiso/Prediction 2026 1.3 Indicate whether each of the descriptions in COLUMN I applies 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 numbers (1.3.1 to 1.3.3) in the ANSWER BOOK. COLUMN I COLUMN II 1.3.1 Pituitary hormone(s) that act on the ovaries during the menstrual cycle A: FSH B: LH 1.3.2 Transmit(s) vibrations from the tympanic membrane to the inner ear A: Ossicles B: Auditory nerve 1.3.3 Plant hormone(s) that cause(s) the stomata to close during drought A: Gibberellins B: Abscisic acid (3 x 2) (6) 1.4 The diagram below represents the human female reproductive system and some of the events that take place in it. A B C D E F G 1.4.1 Identify part: (a) B (1) (b) C (1) 1.4.2 Name the process taking place at: (a) E (1) (b) F (1) 1.4.3 Name the hormone that stimulates the process at E. (1) 1.4.4 Identify the stage of embryonic development at G. (1) 1.4.5 State TWO ways in which part C is suited for the implantation of G. (2) (8) Copyright reserved Please turn over

Life Sciences/P1 7 NSC Prediction Hlayiso/Prediction 2026 1.5 The flow diagram below represents the homeostatic control of the thyroxin level in the blood. Thyroxin level in the blood decreases Gland A is stimulated Gland A secretes more hormone B Hormone B stimulates gland C Gland C secretes more thyroxin Thyroxin level returns to normal 1.5.1 Identify: (a) Gland A (1) (b) Hormone B (1) (c) Gland C (1) 1.5.2 Name the type of mechanism represented in the flow diagram. (1) 1.5.3 State ONE function of thyroxin. (1) 1.5.4 Name the disorder in which gland C becomes enlarged due to a lack of iodine in the diet. (1) 1.5.5 Explain why a person whose diet lacks iodine will have a high level of hormone B in the blood. (2) (8) TOTAL SECTION A: 50 Copyright reserved Please turn over

Life Sciences/P1 8 NSC Prediction Hlayiso/Prediction 2026 SECTION B QUESTION 2 2.1 Read the extract below. THE LEOPARD TORTOISE The leopard tortoise is a large tortoise that lives in the grasslands and savanna of South Africa. After mating, the female uses her hind legs to dig a hole in the soil, where she lays between 5 and 20 eggs with hard shells. She covers the eggs with soil and leaves the nest. The eggs develop in the nest for several months. When they hatch, the young tortoises dig their way out of the nest and must find their own food immediately. In contrast, many frog species release thousands of eggs into water, where the eggs are fertilised. [Summary compiled by the examiner from various sources] 2.1.1 Name the type of fertilisation that takes place in the leopard tortoise. (1) 2.1.2 Name the reproductive strategy, based on where the embryo develops, that is shown by the leopard tortoise. (1) 2.1.3 Explain ONE way in which the egg of the leopard tortoise is suited for the development of the embryo on land. (2) 2.1.4 Explain why the leopard tortoise can produce far fewer eggs than most frog species and still reproduce successfully. (2) (6) Copyright reserved Please turn over

Life Sciences/P1 9 NSC Prediction Hlayiso/Prediction 2026 2.2 The diagram below represents a front view of the human male reproductive system. Bladder A B C D E F G 2.2.1 Identify part: (a) A (1) (b) D (1) 2.2.2 Give the LETTER and NAME of the part that: (a) Produces sperm cells and testosterone (2) (b) Stores sperm cells until they are mature (2) 2.2.3 During a vasectomy, part A is cut and tied on both sides of the body. Explain why a man who has had a vasectomy: (a) Still releases semen during ejaculation (2) (b) Is unable to make a woman pregnant (2) 2.2.4 Explain why a vasectomy does NOT affect the secondary sexual characteristics of the man. (2) (12) Copyright reserved Please turn over

Life Sciences/P1 10 NSC Prediction Hlayiso/Prediction 2026 2.3 The graph below shows the levels of FSH and progesterone in the blood of a woman during one menstrual cycle. 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 0 2 4 6 8 10 12 14 16 Day of the menstrual cycle Hormone level (arbitrary units) Levels of FSH and progesterone during one menstrual cycle FSH Progesterone 2.3.1 On which day was the progesterone level the highest? (1) 2.3.2 Name the structure in the ovary that secretes progesterone from day 16 to day 24. (1) 2.3.3 Describe the relationship between the progesterone level and the FSH level from day 16 to day 20. (2) 2.3.4 Explain the significance of the low level of FSH from day 18 to day 24. (2) 2.3.5 Calculate the percentage increase in the progesterone level from day 16 to day 20. Show ALL your working. (3) 2.3.6 Explain how the progesterone level after day 24 would be different if this woman had become pregnant during this cycle. (3) (12) Copyright reserved Please turn over

Life Sciences/P1 11 NSC Prediction Hlayiso/Prediction 2026 2.4 The diagram below represents a reflex arc. P Q R S T U 2.4.1 Identify part: (a) R (1) (b) U (1) 2.4.2 Give the LETTER of the part that: (a) Converts a stimulus into a nerve impulse (1) (b) Transmits impulses chemically from one neuron to the next (1) 2.4.3 Use ONLY the letters P, Q, R, T and U to show the sequence in which an impulse travels through this reflex arc. (2) 2.4.4 Neuron Q of a person was damaged in an accident. Explain why this person will NOT feel any pain when the finger touches a hot plate and will also NOT pull the hand away. (4) (10) Copyright reserved Please turn over

Life Sciences/P1 12 NSC Prediction Hlayiso/Prediction 2026 2.5 A survey was done on 600 learners, aged 13 to 17 years, at schools in a city. The percentage of learners with short-sightedness (myopia) was determined for groups of learners who spend different amounts of time per day looking at screens (cellphones, tablets and computers). The results are shown in the table below. AVERAGE SCREEN TIME PER DAY (HOURS) LEARNERS WITH SHORT-SIGHTEDNESS (%) Less than 1 12 1 to less than 2 18 2 to less than 3 24 3 to 4 31 More than 4 38 [Data: examiner’s own] 2.5.1 Describe the relationship between the average screen time per day and the percentage of learners with short-sightedness. (2) 2.5.2 Draw a bar graph to represent the data in the table. (6) 2.5.3 Explain why a learner with short-sightedness is unable to see the writing on the board clearly from the back of the classroom. (2) (10) [50] Copyright reserved Please turn over

Life Sciences/P1 13 NSC Prediction Hlayiso/Prediction 2026 QUESTION 3 3.1 The diagram below represents the structure of the human ear. auditory canal A B C D E F G 3.1.1 Identify part: (a) A (1) (b) C (1) 3.1.2 Give the LETTER of the part that: (a) Contains the receptors that are stimulated when the position of the head changes (1) (b) Contains the receptors for hearing (1) 3.1.3 Describe how balance is maintained when a person tilts the head to one side. (4) 3.1.4 When an aeroplane descends quickly, the air pressure in the cabin increases. Passengers often experience ear pain and their hearing becomes muffled. Swallowing or yawning opens part C and relieves these symptoms. Explain how opening part C restores normal hearing. (3) (11) Copyright reserved Please turn over

Life Sciences/P1 14 NSC Prediction Hlayiso/Prediction 2026 3.2 The diagram below represents a longitudinal section through the human brain. A B C D E F G 3.2.1 Identify part: (a) C (1) (b) F (1) 3.2.2 Give the LETTER and NAME of the part that interprets sensations and controls voluntary actions. (2) 3.2.3 A cyclist hit her head in a fall and damaged part E. After the accident she could still think and speak clearly, but she walked unsteadily and her movements were not well coordinated. Explain these observations. (3) (7) Copyright reserved Please turn over

Life Sciences/P1 15 NSC Prediction Hlayiso/Prediction 2026 3.3 Two people, A and B, did not eat for 10 hours. Each person then drank a solution containing 75 g of glucose at time 0. Their blood glucose levels were measured every 30 minutes for 3 hours. NOTE: The normal blood glucose level of a person who has not eaten is between 3,9 mmol/ℓand 5,6 mmol/ℓ. The results are shown in the graph below. 0 30 60 90 120 150 180 0 2 4 6 8 10 12 14 16 Time after drinking the glucose solution (minutes) Blood glucose level (mmol/ℓ) Blood glucose levels of person A and person B Person A Person B [Data: examiner’s own] 3.3.1 Which person (A or B) has diabetes mellitus? (1) 3.3.2 Give TWO reasons from the graph for your answer to QUESTION 3.3.1. (2) 3.3.3 Explain the change in the blood glucose level of person A from 30 minutes to 120 minutes. (4) 3.3.4 Describe how the blood glucose level of person A would be returned to normal if it dropped below 3,9 mmol/ℓafter a long period without food. (3) (10) Copyright reserved Please turn over

Life Sciences/P1 16 NSC Prediction Hlayiso/Prediction 2026 3.4 An investigation was done to determine the effect of the percentage of carbon dioxide in inhaled air on the breathing rate. The procedure was as follows: • Twelve healthy male volunteers, aged 19 to 21 years, took part in the investigation. • Each volunteer sat still and breathed in air containing 0,04% carbon dioxide (normal air) through a face mask for 5 minutes. • The number of breaths taken during the fifth minute was counted. • The volunteers rested for 15 minutes and the procedure was repeated with air containing 1%, 2%, 3% and 4% carbon dioxide. • The average breathing rate of the volunteers was calculated for each percentage of carbon dioxide. The results are shown in the table below. CARBON DIOXIDE IN INHALED AIR (%) AVERAGE BREATHING RATE (BREATHS PER MINUTE) 0,04 14 1 15 2 17 3 21 4 27 [Data: examiner’s own] 3.4.1 Identify the: (a) Independent variable (1) (b) Dependent variable (1) 3.4.2 State TWO variables that were kept constant during this investigation. (2) 3.4.3 State ONE way in which the investigators ensured the reliability of the results. (1) 3.4.4 State ONE ethical requirement that the investigators had to meet before the investigation could start. (1) 3.4.5 State a conclusion for this investigation. (2) 3.4.6 Describe how the body responds to return the carbon dioxide level in the blood to normal when it increases above normal. (5) (13) Copyright reserved Please turn over

Life Sciences/P1 17 NSC Prediction Hlayiso/Prediction 2026 3.5 Blackjack is a broad-leaved weed that grows in maize fields in South Africa. Learners investigated the effect of different concentrations of a synthetic auxin on young blackjack plants and on young maize plants. The procedure was as follows: • Five trays, each containing 20 blackjack plants and 20 maize plants of the same age, were used. • Each tray was sprayed once with 50 mℓof a solution containing a different concentration of the synthetic auxin. One tray was sprayed with water only (0 mg/ℓ). • All the trays were kept in the same greenhouse and watered equally. • After 14 days the percentage of plants of each type that had died was recorded. The results are shown in the table below. CONCENTRATION OF SYNTHETIC AUXIN (mg/ℓ) BLACKJACK PLANTS THAT DIED (%) MAIZE PLANTS THAT DIED (%) 0 0 0 50 25 0 100 60 0 200 100 0 400 100 15 [Data: examiner’s own] 3.5.1 Identify the dependent variable in this investigation. (1) 3.5.2 Explain why one tray was sprayed with water only. (2) 3.5.3 A farmer wants to use this synthetic auxin to control blackjack in his maize field. Which concentration should he use? Use the data in the table to explain your answer. (3) 3.5.4 Explain how a high concentration of auxins causes the death of broad-leaved weeds. (2) 3.5.5 State ONE advantage of using a selective weedkiller rather than removing the weeds by hand. (1) (9) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright reserved