Life Sciences Grade 12 Paper 2 North West Prelim 2024 Memo

Downloaded from hlayiso.com Downloaded from Stanmorephysics.com education Department: Education North West Provincial Government REPUBLIC OF SOUTH AFRICA 150 TIME: 2% hours This question paper consists of 16 pages. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 INSTRUCTIONS AND INFORMATION Read the following instructions carefully before answering the questions. 1. PF ON = © @Onoeaga 11. Answer ALL the questions. Write ALL the answers in the ANSWER BOOK. Start the answer to EACH question at the top of a NEW page. Number the answers correctly according to the numbering system used in this question paper. Present your answers according to the instructions of each question. Do ALL drawings in pencil and label them in blue or black ink. Draw diagrams, tabels or flow charts only when asked to do so. The diagrams in this question paper are NOT necessarily all drawn to scale. Do NOT use graph paper. You must use a non-programmable calculator, protractor and compass where necessary. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 SECTION A QUESTION 4 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 1.1.9) in the ANSWER BOOK, e.g 1.1.10 D. 1.1.1 During which phase of meiosis do homologous chromosomes split and move to the poles? A Anaphase II B Telophase | (o} Anaphase | D Prophase | 1.1.2 The list below describes features of evolutionary theories: (i) Organisms show a great deal of variation (ii) Long periods of time during which species do not change (iii) Frequent use of organs results in them becoming stronger, better and bigger (iv) Favourable characteristics are passed on to the next generation Which ONE of the following combinations of features gives the CORRECT characteristics of natural selection? A (i) and (iv) only B (iii) and (iv) only Cc (ii) and (iii) only D (i) and (iii) only 1.1.3. The table below shows the DNA triplets that code for some amino acids. DNA triplet a: == The anticodon for the amino acid leucine will be ... A ACA. B CUU. Cc GAA. D AGA. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 1.1.4— In humans, brown eye colour is dominant over blue eye colour. When one parent has blue eyes and the other parent has brown eyes and both are homozygous for the trait, what are the chances that their children will have blue eyes? A 100% B 75% Cc 50% D 0% Which ONE of the following monohybrid crosses will result in a phenotypic ratio of 1: 1? A Both parents are homozygous for the dominant characteristic. B Both parents are homozygous. Cc a néte! ozygous and the other parent is D jgous and the other parent is The charact oth humans and African apes are ... A al dimorphism and bipedalism. B ual dimorphism and quadrupedalism. Cc large cranium, small canines and prognathous jaw. D small cranium, large canines and prognathous jaw. The first primate to use tools constantly was ... A Homo neanderthalensis. B Homo sapiens. Cc Homo floresiensis. D Homo habilis. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Bioweweaded from Stanmorephysics.com NW/September 2024 1.1.8 The diagram below represents different phases of meiosis. Diagram 1 Diagram 2 Diagram 3 The sequence in which the phases of meiosis occur are diagrams ... A 1,3 and 2. B 3, 1 and 2. Cc 2, 1 and 3. D 1,2 and 3. 1.1.9 Asample of DNA has 80 guanine bases and 40 adenine bases. How many phosphate molecules would you expect in ONE strand of this sample of DNA? A 40 B 60 Cc 120 D 240 (9x2) (18) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 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. The type of vision present in both apes and humans that allows for depth perception 1.2.2 The monomers of nucleic acids 1.2.3 An explanation describing evolution as consisting of long phases of little change alternating with short phases of rapid change 1.2.4 The phase in the cell cycle during which DNA replication occurs 1.2.5 The type of variation in a population in which there is no range of intermediate phenotype 1.2.6 A sub-group of the hominids that includes only modern humans and early human ancestors 1.2.7. Undifferentiated cells that can develop into any type of cell, tissue or organ 1.2.8 The characteristics that are influenced by alleles carried on the gonosomes 1.2.9 The biotec nological p in of genetically identical offspring ree (9x1) (9) 1.3 Indicate whether nents in COLUMN | apply to A ONLY, B or NONE of the items in COLUMN II. Write A only, B ONLY, BOTH B only, both Aa none next to the question numbers (1.3.1 to 1.3.3) in the ANSWER | COLUMN | COLUMN II 1.3.1 The genotype of a male x¢Y with colour blindness x9x¢d 1.3.2 Evidence of evolution Modification by descent Fossil record Raymond Dart Watson and Crick 1.3.3 Discovered the structure of the DNA molecule DPMP) OS (3x2) (6) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sewevleaded from Stanmorephysics.com NW/September 2024 1.4 The diagram below shows the DNA profiles of a girl, her mother and four males. 1.4.1. Which male is the girl's biological father?’ r Males Girl Mother 7 2 3 7 ees | ey | es | es | ee — ees | ee | ee Se — == == =o == fee | aoe rss Ss = 1.4.2 Explain your answer in QUESTION 1.4.1. 1.4.3 State TWO other functions of DNA profiling. Copyright reserved Please turn over (1) (2) (2) (5)

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 1.5 Some farmers add low doses of antibiotics to the cattle feed which could result in the evolution of antibiotic resistant bacteria. The graph below shows the effect of different doses of antibiotics on the number of harmful bacteria. Effect of different doses of antibiotics on the number of harmful bacteria in live stock 1200 1000 Number of harmful bacteria 2 4 6 8 10 Antibiotic dose (mg) 1.5.1. Name the type of evolution that could result in the evolution of antibiotic resistant bacteria. (1) 1.5.2 Identify the: (a) Independent variable (1) (b) Dependent variable (1) 1.5.3 Describe the trend observed in the graph. (2) 1.5.4 Use evidence from the graph above to explain why higher doses of antibiotics will benefit the farmer economically. fA Copyright reserved Please turn over

Downloaded from hlayiso.com Life Sewevleaded from Stanmorephysics.com 1.6 Albinismis caused by an autosomal recessive allele (a). NW/September 2024 The diagram below shows the inheritance of the albinism in a family. oO John Lizzy Mary | Ha oe) ae Normal male C) Normal female mi Affected * Affected male female KEY : 1.6.1 Give: (a) Mary's phenotype (1) (b) Lizzy’s genotype (1) (c) John’s genotype (1) 1.6.2 Explain why Bob and Ann are both heterozygous for albinism. (2) (5) TOTAL SECTION A: 50 Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 SECTION B QUESTION 2 2.1 The diagram below represents an animal cell in a phase of meiosis. 2.1.1 Name structure: (a) A (1) (b) B (1) 2.1.2 Identify the phase represented in the diagram above. (1) 2.1.3. Give a reason for your answer to QUESTION 2.1.2. (2) 2.1.4 | Which phase occurred before to the one represented in diagram? (1) 2.1.5 Explain the consequences if the process, causing variation, did not occur between chromatids from the cell above. (3) 2.1.6 | How many cells will be formed at the end of this cell division? (1) 2.1.7. Tabulate TWO differences between Meiosis | and Meiosis II (5) (15) 2.2 Lamarck’s theory of evolution is based on TWO Laws or Principles. The Law of use and disuse and the Law of inheritance of acquired characteristics 2.2.1 Explain the Law of inheritance of acquired characteristics according to Lamarckism. (2) 2.2.2 Explain why Lamarck’s ideas are NOT accepted in the science community today. (2) (4) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 2.3 There are four blood groups in humans. Blood group A, B, AB and O are regarded as phenotypes. 2.3.1. Explain why blood groups are controlled by multiple alleles. (2) 2.3.2. How many of these alleles can an individual inherit in the genotype? (1) 2.3.3. Explain the role of blood grouping in paternity testing. (2) (5) 2.4 Scientists wanted to determine what type of genetic disorder are found mostly in cats. To do this they took 200 cats of the same breed suffering from various genetic disorders. The table below represent the types of genetic disorders and percentage of each: a, Percentage of genetic Type of genetic disorders disordars Diabetes 45 Polycystic Kidney Disease 25 Deafness 20 Other 10 2.4.1 Explain the concept gene mutation. (2) 2.4.2 State ONE way in which the reliability of the investigation was achieved. (1) 2.4.3 Draw apie chart to represent the data in the table above. (6) (9) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewevleaded from Stanmorephysics.com 2.5 The diagram below shows the process of protein synthesis. NW/September 2024 aOoGOO—x ‘namo z! Process V Ss 2.5.1 Identify: (a) Process V (1) (b) Two places where molecule X is found (2) (c) Nitrogenous base A (1) 2.5.2 Describe the process occurring at Y. (6) 2.5.3. Give the anticodon for the nitrogenous bases labelled Z. (1) 2.5.4 If the 3% base on the molecule S changed to C, explain the consequences to the protein that will be formed. (3) 2.5.5 The table below shows the amino acids that correspond to different DNA codes. Amino acid DNA code Glycine GGT Arginine TCT Methionine TAC Copyright reserved Write down the sequence from left to right of amino acids coded by molecule S. (3) (17) [50] Please turn over

Downloaded from hlayiso.com Lite Siowleaded from Stanmorephysics.com NW/September 2024 QUESTION 3 3.1 Shrubs of the family Proteaceae can be found in Australia, South America and parts of Africa as shown on the map below. South America : Africa Australia ? 3.1.1. Define the term species. (3) 3.1.2 Explain how the different species of shrubs could have evolved in South America, Africa and Australia. (7) 3.1.3 Mention TWO reproductive isolation mechanisms that keep species separated. (2) (12) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Beweeaded from Stanmorephysics.com NW/September 2024 3.2 The diagrams below represent the pelvic structure and the ventral view of the skulls of three organisms. 3.2.1 Write down the LETTER of the skull that shows a foramen magnum of H. sapiens. (1) 3.2.2 Explain your answer to QUESTION 3.2.1. (2) 3.2.3 Describe how pelvis D is representative of a quadrupedal organism. (2) 3.2.4 Describe TWO visible differences between the jaws of skull K and L. (4) (9) Copyright reserved Please turn over

Downloaded from hlayiso.com Life Bieweleaded from Stanmorephysics.com 3.3 The diagram below shows a possible representation of human evolution. aferensis Ardipithec: Australopithecus .” omo sapiens Homoerectus_ . Homo habilis ecus africanus Paranthropus robustus sis innit iad boisei 45 40 35 30 25 20 15 10 05 0 Million years ago 3.3.1. Name the type of diagram shown above. 3.3.2. How long ago did Australopethicus afarensis become extinct? 3.3.3 Identify TWO species that coexisted with Homo erectus. 3.3.4 State ONE advantage of a larger cranial capacity in H. sapiens. 3.3.5 Calculate the time difference between the evolution of Homo erectus and Homo sapiens. 3.3.6 Describe how the fossils of the species in the diagram provide evidence for the Out of Africa hypothesis. Copyright reserved Please turn over NW/September 2024 (1) (1) (2) (2) (2) (2) (10)

Downloaded from hlayiso.com Lite Boweeaded from Stanmorephysics.com NW/September 2024 3.4 In rabbits, brown fur (B) is dominant to white fur (b) and long ears (E) are dominant to short ears (e). A rabbit that is heterozygous for both characteristics is crossed with a rabbit with white fur and short ears. 3.4.1. How many genes of the rabbits are considered in this cross? (1) 3.4.2 State the genotypes of the parents. (2) 3.4.3 Give: (a) Phenotype of rabbit that is dominant for both characteristics (2) (b) All the possible genotypes in the gametes of the heterozygous parent (2) 3.4.4 State Mendel’s Law of independent assortment. (2) (9) 3.5 Read the information below Familial hypercholesterolemia, a disorder that is passed down through families, causes LDL (bad) cholesterol level to be very high. This disorder shows incomplete dominance. Allele H“ codes for normal LDL receptor. Allele HS codes for the inability to make a LDL receptor. Individuals with genotype HNH" are normal and those with genotype HSHS have severe hypercholesterolemia. Heterozygous (HHS) individuals have a mild form of the disease. 3.5.1 Describe what is meant by incomplete dominance. (2) 3.5.2 Give evidence from the information above that shows that inheritance of familial hypercholesterolemia is an example of incomplete dominance. (2) 3.5.3 A man, heterozygous for familial hypercholesterolemia marries a woman who has normal LDL receptors. In a genetic cross show the percentage chance of them having children with severe hypercholesterolemia. (6) (10) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright Reserved

Downloaded from hlayiso.com Downloadedygrom Stanmorephysics.com education Department: Education North West Provincial Government REPUBLIC OF SOUTH AFRICA SERB BEER BEB REEE BEEBE BEEBE e = s . . . . . . s ¢ rrr ttt tt bd SERB ERE RR RRR RRR RRR ERR MARKS: 148 These marking guidelines consist of 13 pages Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines PRINCIPLES RELATED TO MARKING LIFE SCIENCES 1s 10. 11. 12. 13. 14. 15. If more information than marks allocated is given Stop marking when maximum marks are reached and put a wavy line and ‘max’ in the right-hand margin. If, for example, three reasons are required and five are given Mark the first three irrespective of whether all or some are correct/incorrect. If whole process is given when only part of it is required Read all and credit relevant part. If comparisons are asked for but descriptions are given Accept if differences/similarities are clear. If tabulation is required, but paragraphs are given Candidates will lose marks for not tabulating. If diagrams are given with annotations when descriptions are required Candidates will lose marks. If flow charts are given instead of descriptions Candidates will lose marks. 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. Non-recognised abbreviations Accept if first defined in answer. If not defined, do not credit the unrecognized abbreviation, but credit the rest of answer if correct. Wrong numbering If answer fits into the correct sequence of questions but the wrong number is given, it is acceptable. If language used changes the intended meaning Do not accept. Spelling errors If recognisable, accept the answer, provided it does not mean something else in Life Sciences or if it is out of context. If common names given in terminology Accept, provided it was accepted at the National memo discussion meeting. If only letter is asked for and only name is given (and vice versa) Do not credit. If units are not given in measurements Candidates will lose marks. Memorandum will allocate marks for units separately. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 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 appears 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. 19. No changes must be made to the marking guidelines without consulting the Provincial Internal Moderator. Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines SECTIONA QUESTION 1 1.1 wih Cyvv 5 Se 9 AYvY 177.3 Cvv 1.1.4 Dvv 121:5, Dvv 4; 6 i AJ 14 1 A. (9x2) (18) unctuated equilibriumy 1.2.4 Interphasev 125 Discontinuous” (variation) 1.2.6 HomininsY¥ 1.2.7 Stem cellsY¥ 1.2.8 Sex-linkedv (characteristics) 1.2.9 CloningY (9x1) (9) 1.3 133.1 Aonly¥¥ 1:3,2 Both A and BY ¥ 13.3 B only¥v (3x2) (6) 1.4 1.41 3v (1) 1.4.2 The 2/3 DNA bands/black bars on the DNA profile of male 2/3Y match with the 3 bands on the profile of the girlY (2) 1.4.3 - Identify suspects of crimev - Determine the probability or causes of genetic defects /identify the cures for genetic disorders - Establish the compatibility of tissue types for organ transplants” - Identify missing relatives - To identify dead bodiesY Any (2) (Mark the first TWO only) (5) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 1.5 45.4 Natural selection’ (1) 1.5.2 (a) (Different) doses of antibioticv (1) (b) Number of harmful bacteriaY (1) L543 Higher doses of antibioticY results in lower number of harmful bacteriav OR Lower doses of antibiotic Y result in higher number of numbers of bacteriaY (2) 1.5.4 It decreases the number of harmful bacteriaY the most thereby preventing diseases in the cattlev/resulting in less medical expenses. OR Decreasing mortality of cattlkev by maintaining the number of cattle to sell” /breed/make profit (Mark first ONE only) Any (1 x 2) (2) (7) 1.6 1.6.1 (a) Affectedv female (1) (b) Aav (1) (c) aay (1) 1.6.2 They have an affected son/a son with albinism/son with aa genotype who had inherited one recessive allele from each of the parentsY OR Both Bob and Ann each have parents who are affectedvY and therefore inherited recessive alleles from each parent”. (2) (5) TOTAL SECTION A: 50 Copyright reserved Please turn over

Life Bioweleaded from Stanmorep SECTION B QUESTION 2 2.1 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 2.1.6 2.1.5 Copyright reserved Downloaded from hlayiso.com (a) hysics.com Nw/September 2024 NSC — Marking Guidelines Spindle fibrev/spindle thread (1) Cell membraneY (1) (b) Anaphase I|¥ The centromere splits/spindle fibres contractY and the (two) chromatids are pulled to opposite poles ¥ Metaphase Il “ (1) (2) (1) - Result in similar/same gametesY - offspring of the same genotype and phenotype” being formed - reduced chance of survival/increased chance of extinction and - loss of biodiversityY (Mark first THREE only) Four” /4 Any Tv (3) (1) Meiosis | Meiosis Il Crossing over takes placeY Crossing over does not takeY place Homologous chromosomes arrange at the equator in pairs¥ Chromosomes arrange at the equator singlyY Whole chromosomes move to opposite poles of the cell¥” The chrom umber halved from di oh idv atids move to opposite of the cell ¥ chromosome number! ains the same (haploid) “ Results in two daughte v ults in four daughter ee orern 2x2 +1 for table (5) (15) Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 2.2 2.2.1 The changes/modifications brought about by the frequency of use or disuseY were transmitted/passed on to the offspringY (2) 2.2.2 Organisms do not evolve because they were determined/wanted to change/” but changes took place randomly due to mutationsY (2) OR The characteristics acquired by an organism through use or disuse do not affect the organism's genetic makeupY therefore cannot be inheritedY OR There is no evidence V to show that acquired characteristics are inherited ¥ OR The characteristics acquired by an organism in its lifetime“ cannot be inheritedY (4) 2.3 2.3.1 There are THREE different allele that control inheritance of blood groups Vv ¥ (2) 23.2 2v (1) 2.3.3. It is used to exclude a man from being a child’s fathery v (2) OR To narrow down the possible fathersv ¥ (5) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 24 24.1 The changes to the sequence” of nitrogenous bases in a DNA moleculeY (2) 2.4.2 Used 200V cats (1) 2.4.3 Percentage of genetic disorders in cats Other 10% Diabetes meee 45% PKD ~— 25% Calculations: Diabetes: 45/100 x 360° = 162° PKD 25/100 x 360° = 90° Deafness: 20/100 x 360° = 72° Other: 10/100 x 360° = 36° vv Rubric for marking the graph: Criteria Mark Correct type of graph (T) dAIO | Caption/Heading with 2. (H) 1 variables Correct calculations (C) A2u it | Plotting (P) 1-3correct slices: 1 All four correct slices: 2 (6) (9) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 25 2.5.1_ (a) Transcription’ (1) (b) Nucleus¥ MitochondrionY ChloroplastY Any (2) (Mark the first TWO only) (c) AdenineY (1) 2.5.2 -EachtRNAcarries a specific amino acidY - When the anticodon on the tRNAY - matches the codon on the mMRNAY - then tRNA brings the required amino acid” to the ribosomeY - Amino acids become attached to each other by peptide bondsY - to form the required protein’ Any (6) 2.5.3 GGUY (1) 2.5.4 -the anticodon will change to UAGY instead of UAC - that will code for a different amino acidY - resulting into a change in the (sequence)of amino acidsY - leading to a slightly different structure of protein v Any (3) 2.5.5 Methioninev - glycineY - argininev (in correct sequence) (3) (17) [50] Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines QUESTION 3 3.1 3.1.1 Agroup of organisms sharing the similar/ same characteristicsY that are able to interbreedv to produce fertile” (3) 3.1.2 -The original population of shrubs became separated into three sub- populations” by continental drift/ocean/waterY - no gene flow amongst the (three) sub populations” - each population experienced different environmental conditionsY - and underwent natural selection independentlyY - the shrubs in each population became different” - genotypically and phenotypicallyY - Even if they were to mix again/cross pollinate v’, they will not be able interbreedv /to produce fertile population of shrubs - because they are now three different speciesv” in South America, Africa and Australia 2 compulsory “+ Any 5 (7) 3.1.3 - Species-specific courtship behavior” - Breeding at different times of the yearY - Infertile offspringv - Adaptation to different pollinators” - Prevention of fertilization’ Any (2) (Mark the first TWO only) (12) Copyright reserved Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 32 3.2.4 MY (1) S22 Foramen magnum is in a (more) forward positionY ¥ (2) 3.2.3 It is longY and narrow” (2) 3.2.4 Jaw of skull K is less prognathous/less protruding/non- prognathousv, that of skull L is more prognathous/more protruding/prognathousY The palate of skull K is short and semi-circular/more roundedv , that of skull L Is long and rectangular/U-shapedY The canines of skull K is short~/small, those of skull L is longY/ large and pointed There are no spaces between the teeth/diastema in skull Kv, in skull L there are spaces between the teethv/diastema (Mark the first TWO only) Any (2 x 2) (4) (9) 3.3. 3.3.1 Phylogenetic tree/cladogramv (1) 3.3.2 3,1 /3,0 myav (1) 3.3.3. Homo habilis~” Homo sapiens¥ Paranthropus robustusY Paranthropus boiseiv Any (2) 3.3.4 Increase in brain size/bigger brain sizev v to allow for: Increased intelligence VV storing and cessi ssing of large informationy ¥ information quicklyY ~ Any1x2 (2) 3.3.6 The fossils of Ardipithecus, Australopethicus and Homo habilis are found in Africa onlyY The oldest fossils of Homo erectus and Homo sapiens are found in AfricaY and the youngest fossils are found in other continents (Asia, Europe)” Copyright reserved Any (2) (10) Please turn over

Downloaded from hlayiso.com Lite Biewwweaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines 3.4 3.4.1 Twov/2 (1) 3.4.2 BbEev, bbee Vv (2) 3.4.3 (a) Brown fur with long earsv ¥ (2) (b) BE, Be, bE and bevY (2) 3.4.4 Alleles of different genes segregate/move independently of each othervinto the gamete so that they appear on the gametes in different combinationsY (2) OR The various ‘factors’ controlling the different characteristics are separate entitiesv, not influencing each other in any way, and sorting themselves out independently during gamete formation’ OR A pair of alleles(factors) controlling a particular characteristic separate independentlyY and then recombine differently to form gametesv. (9) 3.5 3.5.1 Neither of the alleles are dominant over each other. An intermediate phenotype is obtained when both alleles are presentY (2) OR Neither one of the two alleles of a gene is dominant over the otherv, resulting in an intermediate phenotype in the heterozygous conditionv . 3.5.2 Individuals with genotype HNHS/heterozygous genotype have a mild form of the disease. Vv’. (2) Copyright reserved Please turn over

315.3 Downloaded from hlayiso.com Lite Rieweleaded from Stanmorephysics.com NW/September 2024 NSC — Marking Guidelines P1 Phenotype Man with x Normal Womanv/ Mild Awoman without hypercholesterolemia hypercholesterolemia Genotype HNHS x HNHN v Meiosis Gametes Fertilization Fi: Genotype nN 4 i 3 HNHSY Phenotype with mild hypercholester: 0%" chance for children with severe hypercholesterolemia P1 and Fiv Meiosis and fertilization V “4 compulsory mark + Any 5 OR P1 Phenotype Man with x Normal Woman v/ Mild Awoman without hypercholesterolemia hypercholesterolemia Genotype HNHS x HNHN vw Meiosis age Gametes HN Hs Fertilization nN a TS HN HNHN | HNHS 1 mark for correct gametes 1 mark for correct genotypes Fi Phenotype 2 Normal individuals/without hypercholesterolemia: 2 Individuals with mild hypercholesterolemiaY O%¥ “chance for children with severe hypercholesterolemia P1 and Fiv¥ Meiosis and fertilization ¥ “4 compulsory mark +Any5 = (6) [48] TOTAL SECTION B: 98 GRAND TOTAL: 148 Copyright reserved