A LEVEL Paper 1 Biology Question Paper 2020/Real Exam/ALL Questions

A LEVEL Paper 1 Biology Question Paper 2020/Real Exam/ALL Questions Answer ALL questions. Write your answers in the spaces provided. Some questions must be answered with a cross in a box . If you change your mind about an answer, put a line through the box and then mark your new answer with a cross . 1 Tay-Sachs disease is a genetic disorder. (a) A couple without Tay-Sachs disease are expecting their second child. Their first child died from the disease. Use a genetic diagram to determine the probability of their second child having Tay-Sachs disease. (2) Answer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (b) Tay-Sachs disease can be detected during pregnancy. Name the prenatal test that could be used to detect Tay-Sachs disease at 11 weeks of pregnancy. (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA lOMoAR cPSD| 3 Turn over Downloaded by charity nimo () (c) Explain why this couple may choose not to have this test.