BIOLOGY Paper 2

AS BIOLOGY Paper 2 Time allowed: 1 hour 30 minutes Materials For this paper you must have: • a ruler with millimetre measurements • a scientific calculator. Instructions • Use black ink or black ball-point pen. • Fill in the boxes at the top of this page. • Answer all questions. • You must answer the questions in the spaces provided. Do not write outside the box around each page or on blank pages. • If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s). • Show all your working. • Do all rough work in this book. Cross through any work you do not want to be marked. Information • The marks for the questions are shown in brackets. • The maximum mark for this paper is 75. Answer all questions in the spaces provided. box . What is a gene? [1 mark] . Describe how the production of messenger RNA (mRNA) in a eukaryote cell is different from the production of mRNA in a prokaryote cell. [2 marks] . Scientists produced a short, single-stranded, artificial nucleic acid, called PNA. The PNA binds to a small section of DNA. The scientists introduced PNA into cells and discovered that these cells produced less mRNA than cells that did not contain PNA. Suggest how PNA affected the transcription of the section of DNA. [2 marks] . Describe the role of ATP in the process of translation in protein synthesis. [2 marks] box Turn over for the next question Turn over ► . What term is used to describe the different structures of α-glucose and β-glucose? [1 mark] box . A student investigated the difference in the reducing sugar content of two fruit juices. He performed a biochemical test on each fruit juice using Benedict’s solution. He then used a colorimeter with each test result. Describe how the results from the colorimeter can identify the fruit juice containing the higher sugar content. [1 mark] 0 2 . 3 The student controlled variables in the test using Benedict’s solution. Give two variables the student controlled. [2 marks] 1