H1_FE_Mark scheme

Civics Group Index Number Name (use BLOCK LETTERS) ST ANDREW’S JUNIOR COLLEGE 2021 JC1 Final Year Examination H1 BIOLOGY 8876/2 Paper 1 & 2: Tuesday October 2021 1hr 45min READ THESE INSTRUCTIONS FIRST Write your name, civics group and index number on all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use a soft pencil for any diagram, graph or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A (Multiple Choice Questions) Answer all 10 questions. For each question, there are four possible answers, A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate multiple choice answer sheet (OTAS). Sections B and C (Structured Questions + Essay) Answer the all 5 questions. Write your answers in the blanks provided. INFORMATION TO CANDIDATES At the end of the examination, 1. Submit the OTAS and question paper separately. Conceptual mistake (C) Expression (E) Data Quoting (D) Misreading the question (Q) For Examiner’s Use Section A /10 Section B 1 /10 2 /10 3 /10 4 /10 Section C 5 /10 Total /60 This document consists of XX printed pages. [Turn over H1

1 SAJC / 9744 / H2 Biology / Final Year Examination 2021 Section A Shade your answers in the OTAS provided. 1 The figure below shows an electron micrograph of a cell. Which row correctly describes structures P – R? P (RER) Q (Mitochondrion) R (nucleus) A synthesis of ribosomes (X) substrate level phosphorylation (true – Krebs cycle occurs in mitochondrion) active replication of genes B provision of large surface area for attachment of ribosomes formation of ATP from light energy (X) active transcription of genes C synthesis of membrane proteins oxidative decarboxylation active transcription of genes

2 SAJC / 9744 / H2 Biology / Final Year Examination 2021 D transport of proteins to Golgi apparatus modification of mRNA transcripts (X) circular DNA in mitochondria, similar to bacterial genes, no post- transcriptional modifications active replication of genes 2 The following are all observations about cell surface membranes. 1 Phospholipids labelled with radioactive phosphate groups change position over time. (√) 2 Proteins labelled with fluorescent dyes change position over time. (√) 3 Lectins are proteins that bind to polysaccharides. They only attach to the outside of membrane samples. (X) This only describes how the membrane is asymmetrical (i.e. inner surface not the same as outer surface). 4 Electron microscope images of membranes fractured b y freezing show a large number of regularly arranged particles interrupted by larger particles. (√) demonstrates the scattered arrangement of proteins in the layer of phospholipids. 5 Some membranes contain more cholesterol and