DECLARATION – By writing this examination, you acknowledge that you are aware of the following: 1.   No copying of any sources is allowed. 2.   All answers must be your own, original work. 3.   Plagiarism is a serious offence and will result in zero marks awarded for the relevant question or section.

Lees die volgende instruksies noukeurig deur voordat jy enige vrae begin beantwoord: 1.       Die antwoorde wat u op die vraestel verskaf moet u eie, oorspronklike werk wees. Geen kopiëring vanaf enige bron word toegelaat nie. Geen punte sal toegeken word vir gekopieerde werk nie. 2.       Lees al die vrae aandagtig deur. 3.       Beantwoord AL die vrae IN die “quiz”. Moenie enige antwoorde oop los nie, en moenie jou antwoorde op papier skryf nie. 4.       Maak gebruik van die puntetoekenning as ʼn riglyn vir hoeveel inligting in u antwoorde gegee moet word 5.       Daar mag ‘n “file upload” vereis word. U benodig ʼn leë vel papier, ‘n liniaal, ‘n pen en ‘n skandeerder, skandeerder-App of selfoon kamera. 6.       Teken slegs diagramme, tabelle en grafieke met die hand op aparte blad wanneer dit so gevra word 7.       Alle diagramme, tabelle en grafieke moet in potlood geteken word, met byskrifte in blou of swart pen. 8.       Die diagramme in hierdie vraestel is nie noodwendig volgens skaal nie. 9.       U mag ‘n sakrekenaar gebruik indien nodig.

3.1.3 The letter N represents the dominant allele and n the recessive allele. Choose the correct genotypes for each of the following individuals: Person Genotypes (a) Their son [a](b) Anne’s uncle [b](c) Mike [c](d) Anne [d] 1.  XNY2.  XnY3.  XNXn4.  XNXN (4)

2.2 A scientist conducted an experiment to determine if a vasectomy (cutting of the male vas deferens) has any influence on testosterone production. He used twelve adult male Giant African rats and divided them into three groups. All rats were tested and have the same testicular weight, sperm count, sperm motility, and testosterone levels at the start of the investigation. A vasectomy was done only on the right testes of the rats in Group 1 and Group 2. Their left testes remained untreated. Group 3 remained completely untreated. After 6 and 8 weeks the testosterone levels in the rats’ blood were tested.  Seminal fluid from both testes was extracted and analysed. The results are shown in the table below. Results of a vasectomy on testosterone levels in Giant African rats Group Treatment Number of weeks between vasectomy and testing Testicular weight (g) Sperm count (x 106/ml) Motility of sperm (%) Testosterone level (ng/ml) R testis Ltestis R testis L testis 1 Vasectomy on right testis 8 weeks 1.75 2.26 0.25 0.35 22 0.65 2 Vasectomy on right testis 6 weeks 2.53 3.22 7.2 14.1 19 1.1 3 Untreated 8 weeks 5.51 5.35 71.0 68.2 83 1.4   Adapted from:  Makerere Medical School, Uganda 2013 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3824497/

2.1.1 Hoeveel spesies word getoon in die prentjie hierbo?  [1] (1)

4.1.6 At 17:00 one participant measured a blood glucose level of 50mg/dL. What could have caused such a big decrease in his blood glucose level? (1)

1.1.5 Which statement regarding nucleotides and nucleic acids is correct? A. Nucleotides are the monomers of nucleic acids.B. Nucleotides are larger than nucleic acids.C. Nucleic acids are the monomers of nucleotides.D. Nucleic acids are found in the nucleus and nucleotides are found in the cytoplasm. (2)

3.2.6 Provide the phenotype results of the following offspring, as a fraction. (a) long wings, grey body(b) longs wings, black body(c) short wings, grey body(d) short wings, black body (4)

2.2.3 (b) Calculate the percentage decrease in sperm count of the left testis in Group 1 as compared to Group 3. Show all calculations, and round off to one decimal place. (3)

2.1.3 Gebruik die prentjie hierbo om die term variasie te verduidelik. Kies die regte terme uit die keuselys hieronder: Al die honde is van [A] spesies.  Steeds is daar is [B] tussen hulle.  Sommiges het lang hare en terwyl ander [C] het. Hierdie [D] word variasie genoem. (4)