Life Sciences Grade 12 P2 Free State Mock 2023 Paper & Memo

Downloaded from Stanmorephysics.com education Department of Education FREE STATE PROVINCE ‘MARKS?150 TIME: 2%2 HOURS This question paper consists of 16 pages.

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. INSTRUCTIONS AND INFORMATION Read the following instructions carefully before answering the questions. 1. 2. 10. 11. AnswenALL the questions. Write-ALL the answers in the ANSWER BOOK. Startthe-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 for each question. ALL drawings should be done in pencil and labelled in blue or black ink. Draw diagrams, tables or flow charts only when asked to do so. The diagrams in this question paper are NOT necessarily 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

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. SECTION A QUESTION 1 1.1 Variousioptions are given as possible answers to the following questions. Choose the answer and write only the letter (A to D) next to the question numbersi(1.1.1 to 1.1.9) in the ANSWER BOOK, for example, 1.1.10 D. 1.1.1 During which phase of meiosis do spindle fibres start to form? A_ Prophase | B_ Metaphase | C_ Anaphase | D_ Telophase | The following list includes some features that are studied in evolution. (i) Bipedalism (ii) Dentition (iii) Brow ridges (iv) Stereoscopic vision Which of these key features separate the human line of evolution from that of the African Apes? A (i) only B (i) and (iv) only C (ii) and (iv) only D (i), (ii) and (iii) only A small section of mRNA has the following sequence of bases that codes for different amino acids: CCC CGU UAA Which ONE of the following is the representation of the anticodons and number of amino acids coded for by this section? ANTICODONS NUMBER OF AMINO ACIDS GGG | GCA AUU 9 GGG | GCA AUU 3 GGG | GCA ATT 9 GGG | GCA ATT 3 lekekele Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 1.1.4 Ina family with four children, each child has a different blood group. The genotypes of the parents must be ... Agr li and 18 i BO/IA 18 and ii @1 IP i and IF BL IF and ii 1.1.5 Which ONE of the following monohybrid crosses where complete dominance applies, will result in a phenotypic ratio of 3:1? A Both parents are heterozygous B One parent is heterozygous, and the other is homozygous recessive C Both parents are homozygous for the dominant characteristic D One parent is heterozygous, and the other is homozygous dominant QUESTIONS 1.1.6 AND 1.1.7 ARE BASED ON THE TIMELINE BELOW SHOWING THE POSSIBLE EVOLUTION OF SOME HOMINIDS: Australopithecus afarensis Homo erectus Time 4 3 2 1 0 (Mya) i I I ! i Ardipithecus Homo Homo ramidus habilis Sapiens 1.1.6 Which species inhabited the Earth for the longest time, and how many years ago did this species appear? A Australopithecus afarensis; 4 mya B Homo erectus; 2 mya C Homo habilis; 2.2 mya D Ardipithecus ramidus; 5mya 1.1.7 How many genera are represented on the timeline above? 0aOW>Y Nawa Copyright reserved Please turn over

(BRowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 1.1.8 The diagram below represents different phases of meiosis. Identify the correct phase in diagram 2 A Anaphase II B_ Metaphase II C_ Prophase | D_ Metaphase | 1.1.9 Ifa DNA molecule contains 20 000 nitrogenous bases, of which 20% are cytosine, how many adenine molecules will be present? A 1000 B 2000 C 6000 D 8000 (9x2) (48) Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 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 JoThe mode of locomotion where an animal uses four limbs 1.2.2UThe bond formed between amino acids 1.2.3-—The part of the skull that houses the brain 1.2.4 Achange in the sequence of nitrogenous bases 1.2.5 A disorder due to the presence of an extra chromosome on the 21° pair of chromosomes in somatic cells of humans 1.2.6 Genetic evidence that is used to support the ‘Out of Africa’ hypothesis 1.2.7. The process by which genetically identical organisms are formed using biotechnology 1.2.8 Type of dominance in which both alleles are expressed in the phenotype 1.2.9 Similar structures that are inherited from a common ancestor and modified for different functions (9x1) (9) 1.3. Indicate whether each of the statements in COLUMN | 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 | COLUMN II 1.3.1 | The genotype ofa person | A: X"Y with haemophilia B: xhxh 1.3.2 | Variation in human height | A: Continuous variation B: Discontinuous variation 1.3.3 | Involved in the discovery of | A: Eldredge DNA molecule B: Gould (3 x 2) (6) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com Grade 12 Prep. Exam. FS/September 2023 1.4 Three ladies each gave birth to a baby boy in a hospital. The babies were accidentally swopped. The diagram below shows a technique used in paternity testing and the results{afeach parent and their baby boys. SMITH STEVENS JONES BABY MR_JIMRS | MR | MRS | MR | MRS 2 3 eee | | —__ a 1.4.1 Identify the technique shown above. 1.4.2. Which baby (1, 2 or 3) belongs to the Smiths? 1.4.3. State TWO other uses for the technique named in QUESTION 1.4.1. Copyright reserved (1) (2) (2) (5) Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 1.5 An investigation was carried out to determine the effect of an antibiotic on bacterial resistance. The diagram shows the effect of an antibiotic on a bacterial population. eg Original Bacterial population betore = treatment with an ap i= = antibiotic ap Ge Gp Key J Resistant Bacteria Bacteria population Gi GD is treated with an antibiotic = = qa a Non-Resistant apapap | tre r || Bacteria population after treated with an antibiotic New bacterial population 1.5.1 Give the: (a) Dependent variable (1) (b) Independent variable (1) 1.5.2 Name the type of evolution that occurs in this—bacterial population. (1) 1.5.3 What is the change in the environment that bringsyabout the change in the bacteria population? (1) 1.5.4 Which variation can be found in greater proportion in the final population? (1) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 1.5.5 What percentage of the bacteria in the original population was resistant to antibiotics? (1) (6) 1.6 A genetic disorder is caused by a recessive allele (a). An individual with the disorder is described as affected, and an individual withoutflis described as unaffected. The affected individual is indicated by a black-Gircle or square. The ‘pedigree diagram below shows the inheritance of this disorder in a ae a a 1.6.1 How many of each of the following are present in the diagram? (a) Males (1) (b) Generations (1) (c) Children of individuals A and B (1) 1.6.2 Give the: a) Possible genotype of individual D (2) b) Phenotype of individual C ( TOTAL SECTION A: 50 Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. SECTION B QUESTION 2 2.1 The diagram below represents chromosomes in a cell that is undergoing meiosis! a —_ B c A 2.1.1 Identify: (a) Chromosome pair A (1) (b) Structure B (1) (c) Partc (1) 2.1.2 Which process is illustrated in the diagram? (1) 2.1.3. During which phase of meiosis does the process named in QUESTION 2.1.2 take place? (1) 2.1.4 What is the importance of the process named in QUESTION 2.1.2? (1) 2.1.5 Describe ONE other process in meiosis which will ensure the same outcome as the one stated in QUESTION 2.1.4. (3) (9) 2.2 Tabulate THREE differences between meiosis | and)méiosis II. (7) (7) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com Grade 12 Prep. Exam. 2.3 2.4 2.5 Copyright reserved Lamarckism refers to the theory of evolution suggested by Jean Baptiste de Lamarck. Answer the following questions on Lamarck's theory. 2.3.1 OState the TWO principles (laws) that Lamarck used to explain evolution. 2.3.2—€Explain ONE reason why most scientists reject this theory. Human blood types are determined by multiple alleles. Fach person has only two alleles in their DNA that code for their blood type. Explain how an analysis of blood groups can be used to determine paternity. Scientists wanted to determine which type of inheritance accounted for most of the selected genetic disorders in dogs. To do this they sequenced the genomes of many dogs of the same breed that suffered from the genetic disorders. FS/September 2023 (2) (4) (5) (5) The table below represents the type of inheritance for genetic disorders in dogs. TYPE OF PERCENTAGE OF GENETIC INHERITANCE DISORDERS (%) Autosomal recessive 71 Autosomal dominant 11 Sex-linked 10 Other 8 2.5.1 Define the term genome. 2.5.2 State ONE factor that was kept constant in this investigation. 2.5.3. Draw a pie graph to represent the information provided in the table. (2) (1) (6) (9) Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 2.6 The diagram below shows parts of two different processes that take place in the nucleus and a process taking place at the ribosome. Ribosome 2.6.1 Identify: (a) Molecule A (1) (b) Organelle B (1) (c) Molecule C (1) (d) The number of codons shown in the diagram onthe mRNA (1) 2.6.2 Give the anticodon for the second codon from left to right. (2) 2.6.3 Name AND describe the process that is taking place at X. (6) 2.6.4 Describe the role of mRNA in protein synthesis. (4) (16) [50] Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. QUESTION 3 3.1. The baobab tree belongs to the genus Adansonia. Different species are found in Africa and Australia. Originally these two continents formed part of Gondwanaland, as shown in the diagram below. / Gondwanaland Ocean \ African baobab f Australian baobab different continents. (6) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com Grade 12 Prep. Exam. 3.2 3.3 Copyright reserved Read the extract below on a group of birds. Warblers/songbirds belong to a large group of birds grouped together in the_same bird family. In Siberia, Russia, two distinct species of greenishiwarblers coexist, one in the west and one in the east. A large region-of desert, where they cannot survive, separates the two groups of warblers. Their distributions only narrowly overlap in central Siberia, where-they do not interbreed. The two species differ, in the songs that males sing to attract females. Also, females of each species do not recognize the song of the other species but respond strongly to the song of the males from their own species. 3.2.1 Name AND describe the reproductive isolation mechanism described in the extract. 3.2.2 Mention TWO other reproductive isolation mechanisms that keep species separated. The diagrams below show the pelvic structure of two species not drawn to scale. 3.3.1. Which diagram represents the pelvis of a hominid? 3.3.2 Explain ONE reason why Diagram B is better suited for a bipedal mode of locomotion. 3.3.3. Explain TWO advantages of bipedalism. FS/September 2023 (2) (5) (1) (2) (4) (7) Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 3.4 The diagrams below represent the side and ventral views of the skulls of three primates: A gorilla, Australopithecus africanus and Homo Sapiens. The diagrams showing the side views are not necessarily in the same order as the diagrams showing the ventral views. Side view) 3.4.1. Name the family that all these primates belong to. (1) 3.4.2. Which diagram (I, Il or Ill) represents the ventral view of skull B? (1) 3.4.3. Give TWO visible reasons for your answer to QUESTION 3.4.2. (2) 3.4.4 Describe THREE visible differences between thesjaws in diagrams Il and III, which show trends in human evolution. (6) 3.4.5 Based on the differences in dentition, what conclusion can be made about the difference in the diet of the organisms in diagrams II and III? (2) (12) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. 3.5 3.6 In guinea pigs, black fur (B), is due to a dominant gene and white fur (b) is due to a recessive gene. Short fur (H) is due to a dominant gene and long fur (h) is due to a recessive gene. A breeder made the following cross: BbHh x bbhh 3.5.1 3.5.2 3.5.3 3.5.4 State the phenotypes of the parents that the breeder crossed. (2) Give the genotypes of ALL the possible gametes of the parents. (2) Give : a) All the possible phenotypes of the offspring (2) b) The dominant allele for fur colour (1) Explain Mendel's law of independent assortment. (10) Study the extract below on the characteristics of fruit flies. Female fruit flies are approximately 2,5 mm long. Males are smaller and possess a distinct black patch on their bodies. Females lay up to 400 eggs, which develop into adults in 7 to 14 days. Fruit flies can survive and breed in small flasks containing a simple nutrient medium consisting mainly of sugar. The gonosomes of fruit flies are similar to that of humans (XX and XY). 3.6.1 3.6.2 Explain TWO reasons why the fruit fly is a useful organism for studying genetic crosses. (4) In fruit flies, the gene for eye colour is sex-linked and is carried on the X chromosome. The allele for red eyes R is dominant to the allele for white eyes r. A male with white eyes is crossed with a homozygous female with red eyes. Use a genetic cross to show the phenotypic ratio.of the F1 offspring. (6) (10) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright reserved

Downloaded from Stanmorephysics.com education Department of Education FREE STATE PROVINCE PREPARATORY EXAMINATION GRADE 12 LIFE SCIENCES P2 SEPTEMBER 2023 MARKS: 150 MARKING GUIDELINES This marking guideline consists of 12 pages. Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines PRINCIPLES RELATED TO MARKING LIFE SCIENCES 1. 10. 11. 12. 13. 14, If more information than marks allocated is given Stop marking when maximum marks are reached and put a wavy line and 'max' in the righthand margin. If, for example, three reasons are required and five are given Mark the4irst three irrespective of whether all or some are correct/incorrect. If the whole process is given when only a part of it is required Read all and credit the relevant part. If comparisons are asked for, but descriptions are given Accept if the 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 the 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 the sequence and links become correct again, resume credit. Non-recognised abbreviations Accept if first defined in the answer. If not defined, do not credit the unrecognised abbreviation, but credit the rest of the answer, if correct. Wrong numbering If the answer fits into the correct sequence of questions, but the wrong number is given, it is acceptable. If the language used changes the intended meaning Do not accept. Spelling errors If recognisable, accept the answer, provided it does not meah-something else in Life Sciences or if it is out of context. If common names are given in terminology Accept, provided it was accepted at the national memo discussion meeting. If only the letter is asked for, but only the name is given (and vice versa) Do not credit. Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 15. 16. 17. 18. 19. If units are not given in measurements Candidates will lose marks. Memorandum will allocate marks for units separately. Be sensitive to the sense of an answer, which may be stated differently. Caption All illustrations (diagrams, graphs, tables, etc.) must have a caption. Code-switching of official languages (terms and concepts) A single word or two that appear(s) in any official language other than the learner's 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 applies to all official languages. Changes to the memorandum No changes must be made to the memorandum. The provincial internal moderator must be consulted. Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines SECTION A QUESTION 1 14 Avy Divv By v AvY Avy BY Bvv Dvv Cvv (9 x 2) Sa Ce es CC pa Oa Oe CO OMONMANBRWNH > 1.2 Quadrupedalismv” Peptidev Craniumyv Gene mutation” Trisomy 21v/Down Syndrome Mitochondrial DNAV /mt-DNA Cloning” Co-DominanceY Homologous structures” (9x1) Sa Cs CO Ce CC OMONDNAWNH = 1.3 Both A and Bvv A onlyvv NonevY (3 x 2) aos Wn 14 = a DNA profiling” Fa iN) Baby 3vv 1.4.3 — Identifying suspects in a crimev — Tracing missing personsY — Identifying genetic disorders” — Matching tissues for organ transplantsY — Identifying dead personsv (Mark first TWO only) Any 1.5. 1.5.1 (a) Bacterial resistancev (b) Effect of antibioticsw” 1.5.2 Natural SelectionY/Punctuated Equilibrium 1.5.3 Antibiotics’ 1.5.4 Resistant Bacteriav 1.5.5 25%v (18) (9) (2) (5) (1) (1) (1) (1) (1) (1) (6) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com Grade 12 Prep. Exam. Marking Guidelines 16 161 a)5v b) 3v c) 3v 1.6.2 lay Aav /AAY b) Affected femalev SECTION B QUESTION 2 2.1. 2.1.1. (a) Homologousv chromosomes/bivalent (b) Centromerev’ (c) ChromatidY 2.1.2 Crossing overY 2.1.3. Prophase Iv 2.1.4 Ensures genetic variation’ FS/September 2023 (1) (1) (1) (2) (1) (6) TOTAL SECTION A: 50 (1) (1) (1) (1) (1) (1) 2.1.5 — Chromosomes/chromatids arrange themselves randomly” — oneither side of the equatorv — during metaphase I|v‘/II Copyright reserved (3) (9) Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 2.2 Meiosis | Meiosis Il Crossing over takes placer | No crossing over takes placev In metaphase, the (In metaphase) chromosomes align on the chromosomes align singlyw equator in homologous on the equator ‘pairsY During anaphase, During anaphase, chromosomesY move chromatidsv move towards towards the poles the poles Homologous chromosomes Chromosomes occur singly in prophase | v in prophase Il v The chromosome number is_ | The chromosome number halvedv/changes from remains the samev diploid to haploid Results in two daughter Results in four daughter cellsv” cellsv” (7) (Mark first THREE only) Any 3 x2 +1 for table 2.3. 2.3.1 'Law' of use and disuse” ‘Law' of the inheritance of acquired characteristics” (2) 2.3.2 -— Acquired characteristics” — are not inheritedv/do not cause any change to the DNA of an organism's gametes (2) (4) 2.4 — The blood the of mother, possible father and the child must be comparedv’ — If this shows that it is not possible that these parents can produce a child with his/her blood groupY — then this man is not the fatherv — If this shows that it is possible that these parents can produce a child with his/her blood groupY — then he may/ may not be the father — because other males have the same blood group” (5) Any (5) 2.5 2.5.1 The mapping of the exact position of all the genes in all the chromosomes of an organism/humanv v (2) 2.5.2 The breed of the dogsY (Mark first ONE only) (1) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com Grade 12 Prep. Exam. Marking Guidelines 2.5.3 Calculations Total: 71 + 11 + 10+ 8 = 100 Autosomal recessive: 71/100 x 360 = 255.6° autosomal dominant: 11/100 x 360 = 39.6° Nn pattinses 10/100 x 360 = 36° er: 8/100 x 360 = 28.8° FS/September 2023 PERCENTAGE GENETIC DISORDERS CAUSED BY DIFFERENT TYPES OF INHERITANCE IN DOGS Other 8% Sex -linked 10% Autosomal dominant 11% Criteria for marking graph CRITERIA Pie chart drawn (T) Caption showing the relationship between the two variables(H) Correct calculation (C) to determine the proportions for the labelled sectors Plotting of Sectors (P) Correct proportions for labelled sectors 1-3 sectors drawn and labelled correctly All 4 sectors of the graph are drawn and labelled correctly Copyright reserved Autosomal recessive 71% (6) (9) Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 2.6 2.6.1 (a)DNAY (1) (b) NucleolusY (1) (c) tRNAY (1) (d) 3v (1) 2.6.2—UCCvv (2) 2.6.3. DNA Replication’* 264 - Copyright reserved The DNA (double helix) unwinds” and unzipsv/hydrogen bonds break to form two separate strandsv Both DNA strands serve as the templatesY to build a complementary DNAv/(A to T and C to G) using free (DNA) nucleotides” from the nucleoplasm This results in two identical (DNA) moleculesY Each molecule consists of one original strand and one new strand¥ *4 Compulsory + Any 5 mRNA forms during transcription’ by copying the coded message from DNAY and moves out of the nucleusY and attaches to the rilbosomeY the anticodons on the tRNA match the codons on the mRNAY Any (6) (4) (16) [50] Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines QUESTION 3 3.1 — The common ancestor of the original baobab population/the baobab population of Gondwanaland was separated into two populationsY 4! by the ocean/seav* - There was no gene flow between the African baobab and Australian baobabv /two baobab populations. — Each baobab population were exposed to different environmental conditions~/other selection pressures. — Natural selections occur independentlyv in each of the two baobab populations. — Such that the individuals of the two baobab populations become very differentv from each other. — genotypically and phenotypically” — even if the two baobab populations were to mix again’ — they will not be able to interbreed.v The two baobab populations are now different baobab species (in the question) (No marks for this statement) *4 Compulsory + Any 5 (6) 3.2 3.2.1. — They use species-specific courtship behaviour”* - Males sing songs to attract female matesY — and females do not respond/recognise songs from other males¥ *4 Compulsory + 2 (3) 3.2.2 — Breeding at different times of the yearY — Plant adaptations to different pollinators” — Producing infertile offspring” — Prevention of fertilisation” (Mark first TWO only) Any (2) (5) 3.3 3.3.1 BY (1) 3.3.2 — The pelvis is short and widev — to support the body weight of the upper body” (Mark first ONE only) (2) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 3.3.3. — Frees the armsv so that they could carry offspring /tools/food/manipulate things - Allows the ability to see furtherv to spot dangerv /food 4! Reduces the surface area exposed to the sun,” so, less heat is absorbed /less heat lost/improved thermoregulation — Expose the genitalsv to attract the opposite sexv — Efficient locomotion’ allows travelling longer distances” (Mark first TWO only) Any 2x2 (4) (7) 3.4 3.4.1 Hominidaev (1) 3.4.2 Diagram IIlv (1) 3.4.3. - The foramen magnum is in a more forward position’ — The palate is more roundedv (Mark first TWO only) (2) 3.4.4 -— The jaw/palate is rectangular in Diagram IlV and rounded in Diagram IIlv — Large spaces between the teeth in Diagram IIV and small/ no spaces between the teeth in Diagram IIIv — Large canines/teeth in Diagram Il v and small canines/ teeth in Diagram III ~ (Mark first THREE only) Any 3x2 (6) 3.4.5 — This organism in Diagram II had a diet of hard, raw foodv — and the organism in Diagram Ill has a diet of softerv’/ cooked food (2) (12) 3.5 3.5.1 Phenotype Black short fur” x White long fur” (2) 3.5.2 Gametes BH, Bh, bH, bhYY (2) 3.5.3 (a) Black Short fur; Black Long fur; White Short fur; White (2) Long fury ¥ (1) (b) Black fur” Copyright reserved Please turn over

(Bowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 3.5.4 — Because of the random arrangement of chromosomes at the equator during meiosis“/any one of two alleles of a characteristic can sort with any two of another characteristic — the alleles of different genes move independently of each other into the gametes” “! They can therefore appear in the gametes in different combinations” (3) (10) 3.6 3.6.1 — Females lay many eggs” which will ensure that the ratios obtained will be reliable — The eggs develop very quicklyv’/7 to 14 days therefore, results will be obtained fast’ — Can clearly differentiate between male and femaleY making it easy to breedv — Fruit flies survive and breed in small flasks” making it easy to observe and work withv — The food medium required is simplev/cheap making it easy/cheap to conduct the investigation’ (Mark first TWO only) (Any 2 x 2) (4) Copyright reserved Please turn over

(Rowsleaded from Stanmorephysics.com FS/September 2023 Grade 12 Prep. Exam. Marking Guidelines 3.6.2 P1Phenotype: White-eyed male x red-eyed femalew Genotype: X'Y x XRXR Meiosis G/gametes x, Y XR | XR v Fertilisation F; Genotype xRxr XRXT XRY XRY w Phenotype: 2 red-eyed males : 2 red-eyed females 1 red eyed male : 1 red-eyed femalev* P; and F1 ¥ Meiosis and fertilisation v (*1 Compulsory + Any 5) OR P1 Phenotype: White-eyed male x Red-eyed femalev Genotype: x'Y x XRXR v Meiosis Gametes xR XR x" xR xt xR xt Fertilisation Y XRY XRY 1 mark for correct gametes” 1 mark for correct genotypesY F1 Phenotype: 2 red-eyed males: 2 red-eyed females 1 red-eyed male: 1 red-eyed femalev* P; and Fi ¥ Meiosis and fertilisation v (*1 Compulsory + Any 5) — (6) (10) [50] TOTAL)SECTION B: 100 GRAND TOTAL: 150 Copyright reserved