Life Sciences Grade 12 Paper 1 Free State June 2025 Memo

education Department of Education FREE STATE PROVINCE GRADE 12 LIFE SCIENCES JUNE 2025 TOTAL: 150 MARKING GUIDELINES These marking guidelines consist of 9 pages. Copyright reserved Please turn over

Life Sciences Examination Paper 1 2 June 2025 Grade 12 Marking Guidelines PRINCIPLES OF MARKING LIFE SCIENCES 1. 10. 11. 12. 13. 14. If more information than the mark allocation is given Stop marking after the maximum points have been obtained and draw a squiggly line indicating ‘max’ points in the right hand margin. If, for example, three reasons are required and five are given. Mark only the first three regardless of whether all or some are correct/incorrect. If the whole process is described while only a part is required Read everything and credit the relevant parts. If comparisons are required but descriptions are given Accept if the differences/similarities are clear. If tabulation is required and paragraphs are given Candidates will forfeit marks if not tabulated. If annotated diagrams are presented instead of descriptions required Candidates will forfeit marks. If flowcharts are presented instead of descriptions Candidates will forfeit marks. If the sequence is vague and links do not make sense Credit where sequence and links are correct. Where sequence and links are not correct, do not credit. If the sequence is correct again, continue to credit. Unrecognized abbreviations Accept if it is described at the beginning of the answer. If it is not defined, do not credit the unrecognized abbreviation, but credit the rest of the answer if it is correct. Wrongly numbered If the answers match the correct order of the questions, they are acceptable. If the language used changes the intended meaning Don't accept. Spelling errors Accept if recognizable, provided it does not mean something else in Life Sciences or is out of context. If common names are given in terminology Accept, if accepted at the memo discussion. If only letter is required and only the name is given (and vice versa) No credit. Copyright reserved Please turn over

Life Sciences Examination Paper 1 3 June 2025 Grade 12 Marking Guidelines 15. 16. 17. 18. If units of measure are not indicated Candidates will forfeit marks. Memorandum will indicate separate points for units. Be sensitive to the meaning of the answer, which can sometimes be presented in different ways Heading All illustrations (such as diagrams, drawings, graphs, tables, etc.) must be captioned. Mixing of official languages (terms and concepts) Asingle word or two in any other official language other than the learner's language of assessment in which most of his/her answers are presented must be credited, if correct. A marker proficient in the relevant official language should be consulted. This applies to all official languages. Copyright reserved Please turn over

Life Sciences Examination Paper 1 Grade 12 SECTION A QUESTION 1 11 11.1 1.1.2 1.1.3 1.1.4 1.15 1.1.6 1.1.7 1.1.8 1.1.9 1.2 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.2.9 1.3 1.3.1 1.3.2 1.3.3 1.4 1.4.1 1.4.2 15 1.5.1 1.5.2 15.3 Copyright reserved Byv CvyY BYY Cvv BYY BYY CvvY Dvv Dvv EpididymisY Internal fertilisation” Parental careY Diabetes mellitus OvariesY SynapseY MorulaY PubertyY Chorionic villi” B only ¥V¥ B only V¥ B only V¥ (a) DY TestisY (b) CY UrethraY (c) AY Cowper gland¥ Testosterone ¥ (a) BY Corpus callosum¥ (b) DY Medulla OblongataY (c) AY Cerebrum¥ - Brain’ - Spinal cordY (Mark first TWO only) - Cranium¥ - MeningesY - Cerebrospinal fluid¥ (Mark first TWO only) 4 Marking Guidelines June 2025 (9x 2) (18) (9x1) (9) (3x 2) (6) (2) (2) (2) (1) (10) (2) (2) (2) (2) Any (2) (10) TOTAL SECTION A: 50 Please turn over

Life Sciences Examination Paper 1 5 Grade 12 Marking Guidelines SECTION B QUESTION 2 21 2.2 2.3 2.4 Copyright reserved 2.1.1 External¥ June 2025 (1) 2.1.2 - 100 eggs arereleased” because the ova can be washed away” /eaten by predators - The male grasp onto the female” so that the sperm is release on the ova” /in proximity of the ova. - Eggs are imbedded in the back of the female” to protect the eggs from predators Any (4) (Mark first TWO only) 2.1.3. OviparyY 2.2.1 (a) OvumY (b) Ovulation’ (c) LH” /(luteinising hormone) 2.2.2 - OvarianY cycle - Uterine” cycle (Mark first TWO only) 2.2.3. Hormone B/Progesterone decreases to 28 days The corpus luteum disintegrate ¥ (Mark first TWO only) 2.2.4 - Diploid cells in the ovary undergo mitosis” - to form numerous follicles” - Atthe onset of pubertyY - and under the influence of FSHY - one cell inside a follicle enlarges and undergoes meiosisY - Of the four cells that are produced, only one survives - to forma mature, haploid ovum¥ - This occurs ina monthly cycleY - The point of attachment to the mother” (Mark first FOUR only) 2.4.1 Spinal cordY 2.4.2 Rapid”, automatic” reaction to a stimulus” (1) (6) (3) (2) (2) Any (5) (12) Any (4) (1) (3) Please turn over

Life Sciences Examination Paper 1 6 Marking Guidelines Grade 12 25 2.6 2.4.3 2.4.4 2.4.5 2.5.1 2.5.2 2.5.3 2.5.4 2.6.1 Copyright reserved Neuron Al Sensory neuron Neuron D/ Motor neuron Monopolar neuron”/ One outgrowth from the cell body Multipolar neuronY/ Multiple outgrowths from the cell body Both the dendrite and axon cover with a myelin sheath Only the axon is covered with a myelin sheath The dendrites are long and the axon is short” The dendrites are short, and the axon are long” The cell body is in the middle of the neuron The cell body is at the end of a neuron (Mark first TWO only) - The spinal cord shortens the reaction time by sending June 2025 Any (2 x 2) + (1) table” impulses directly to the effector” - If the brain is involved, it delays the reaction” - Causing injury“ /being burned (Mark first TWO only) - This will cause a slow transmission of impulsesY¥ - The myelin sheath is damaged” by multiple sclerosis - Resulting in a slow reaction timeY Oestrogen and progesteroneY - The controlv” - to ensure that oestrogen and progesterone are responsible for the thickening of the endometrium ¥ - same dietY - same exerciseY - same ageY - same period”/ of 10 days - healthy humans¥ (Mark first TWO only) (5) Any (2) (3) (14) (1) (2) Any (2) Oestrogen and progesterone increase the thickness of the of progesterone. ¥ ¥ endometrium more than only (a) CristaY MaculaeY (b) SensoryY neuron (2) (7) (2) (1) Please turn over

Life Sciences Examination Paper 1 7 June 2025 Grade 12 2.6.2 2.6.3 QUESTION 3 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.2 3.2.1 3.2.2 3.3 Copyright reserved Marking Guidelines Preventing echoes from forming Absorb excess pressure waves from the innerear Any (Mark first ONE only) (1) - The organ of Corti will be stimulated” - Toconvert the pressure waves” to - impulses¥ (3) (7) Total Question 2 [50] (a) Aqueous humourY (2) (b) CorneaY (4) (c) Retina” (2) - Elastic” The lens changes shape to allow for accommodationY - ConvexY To focus on light rays on the retina refraction - TransparentY To allow light to pass through” to the retina Any (2x2) (4) (Mark first TWO only) - The circular muscles relaxY and - The radial muscles contract¥ - The pupil dilatesv /diameter enlarger - Sothat more light enters the eye” - Tobe focused on the retinaY (5) - Ciliary muscle contract¥ - Ciliary body move towards lensv - Suspensory ligaments slacken (loosen) - Tension on the lens decreases¥ - Lens become more convex” - This causes light rays to bend moreY - to focus on the retina” and form a clear image (6) (18) Short-sightednessY /myopia (1) The eyeball is to round /cornea is too convex so the light rays are refracted more and the light rays focus in front of the retinaY and not on the retina, so no clear image is formed (2) (3) Multipolar neuron 2 turn over Nucleus Dendrites Myelin sheath dhe

Life Sciences Examination Paper 1 8 June 2025 Grade 12 Marking Guidelines Heading of the diagram (C) 1 Correct type of diagram/neuron__(T) 1 Any 1 label (L) 1 Any 2 label (L) 2 Any 3 labels (L) 3 (5) 3.4 3.4.1 (a) AY - Pituitary gland”/Hypothesis (2) (b) BY - Thyroid glandY (2) (c) DY - PancreasY (2) 3.4.2 (a) FSHY (1) (b) Growth hormone” /GH (4) (c) GlucagonY (1) 3.4.3 GoiterY (1) 3.4.4 Pancreases secrete pancreatic juice ¥/enzymes through duct¥ Pancreases secrete hormones /(insulin and glucagon) directly in the bloodY Any (2x2) (4) (14) 3.5 3.5.1 - Chemical messengersY - Proteins¥ (Organic Compound) - Small quantities neededY - Transport to target organs¥ Hormones are stimulatory or inhibitory” Any (3) (Mark first THREE only) 3.5.2 Adrenalin’ (1) Copyright reserved Please turn over

Life Sciences Examination Paper 1 9 June 2025 Grade 12 3.5.3 Marking Guidelines Increases heart ratev leading to a increased blood pressure supplies more glucose and O> for cell respirationY Stimulates the liver to convert more glycogen into glucose” to provide more glucose for cell reparation” Blood supply to the skeletal muscles and heart muscle increases” so that muscle cells get more glucose and O2 for cell respiration’ Pupils dilateY~ and more light enters the eye to focus the light rays on the retina to form a clear image¥ Blood vessel in skin narrows¥ /vasoconstriction and less blood goes to skin and intestines and more blood to the muscle cells for cell respiration” Breathing rate and depth increaseY to supply more O> for cell respiration” Body cellsY — Increased metabolic rateY Any (2x3) (Mark first THREE only) Total Question 3: TOTAL SECTION B: GRAND TOTAL: