In phenylketonuria:
Correct answer: A. Phenylalanine hydroxylase is not formed
- A. Phenylalanine hydroxylase is not formed
- B. Phenylalanine hydroxylase is not degraded
- C. Phenylalanine is not formed
- D. Adenosine deaminase is not formed
Explanation
Phenylalanine hydroxylase enzyme is required to degrade phenylalanine. As a result phenylalanine accumulates in the cells leading to mental retardation, as the brain fails to develop in infancy. So synthesis of phenylalanine hydroxylase is inevitable and any mutation causing its deficiency will result in a disease called phenylketonuria.
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About Inheritance
Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.
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