Question

Garrod hypothesized that "inborn errors of metabolism" such as alkaptonuria occur because... A. genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes. B. enzymes are made of DNA, and affected individuals lack DNA polymerase. C. many metabolic enzymes use DNA as a cofactor, and affected individuals have mutations that prevent their enzymes from interacting efficiently with DNA. D. certain metabolic reactions are carried out by ribozymes, and affected individuals lack key splicing factors. E. metabolic enzymes require vitamin cofactors, and affected individuals have significant nutritional deficiencies.

Answer 1

Garrod hypothesized that "inborn errors of metabolism" such as alkaptonuria occur because...genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes.

Explanation:

Archibald Garrod researched on alkaptonuria and proposed the ‘one gene-one enzyme’ hypothesis. This led to the finding that alkaptonuria is caused due to an inherited or “inborn error of metabolism”.

This hypothesis stated that each gene codes and responsible for a single specific enzyme which facilitates a particular step in the metabolic processes.

According to Garrod, a mutation of a particular gene leads to specific error or defect leading to a lack of a particular enzyme that takes part in the biochemical metabolic pathways. This disrupts the metabolic pathway at the specific enzymatic action point.

In alkaptonuria, it was found that the defective phenotype of dark urine is due to the inborn error happening during the waste elimination process.