Page 07 13. The diagram below shows possible outcomes for a cell following DNA damage. Protein X is involved in all three outcomes. DNA Damage Protein X DNA Repair Cell Cycle Arrest Apoptosis Protein X is A Rb B p53 C Cdk D caspase. 14. Two reagents used in testing for the presence of carbohydrates are iodine solution, which turns blue-black in the presence of starch, and Benedict’s solution, which turns brick red in the presence of maltose. In an investigation of the breakdown of starch into maltose by the enzyme amylase, which of the following would be a positive control? A Maltose alone turns Benedict’s solution brick red. B Starch treated with amylase turns Benedict’s solution brick red. C Starch alone tested with Benedict’s solution remains blue. D Starch treated with amylase does not change the colour of iodine solution. [Turn over