
Defect in amino acid metabolism may result in.
(a) Porphyria
(b) Phenylketonuria
(c) Wilson’s disease
(d) Tay Sach’s disease
Answer
466.5k+ views
Hint: The disorder that causes a defect in the amino acid metabolism occurs due to mutations in both the alleles of a gene that is present on chromosome number 12. Due to this mutation, the enzyme required for amino acid metabolism is not produced.
Complete Answer:
The defect in the metabolism of the amino acid phenylalanine results in Phenylketonuria. Phenylketonuria PKU is an autosomal recessive disorder i.e. it is inherited from parents to children. This happens due to a mutation on chromosome 12 because of which the enzyme phenylalanine hydroxylase (PAH) is not produced in the body. This enzyme is responsible for converting phenylalanine into tyrosine and in its absence phenylalanine gets accumulated. This further gets converted into phenyl pyruvic acid which causes mental retardation.
Additional information: Let us look at the other disorders mentioned in the options.
Porphyria: It is a type of liver disorder in which a compound named porphyria gets accumulated in the body resulting in the deterioration of the skin and nervous system.
Wilson’s disease: It is a type of genetic disorder in which there is excess copper metal build up in the body which affects the functioning of the brain and the liver.
Tay Sach’s disease: It is also a genetic disorder that results in the destruction of nerve cells present in the brain and the spinal cord which results in the loss of the ability to sit, walk or even crawl.
So, the correct option is ‘(b) Phenylketonuria’.
Note:
- Phenyl pyruvic acid is excreted through the urine as well because of their poor absorption by the kidneys.
- Other autosomal recessive disorders include sickle cell anemia in which the RBC becomes sickle-shaped due to a mutation in the hemoglobin.
- Another autosomal recessive disorder is thalassemia which is also a blood disorder caused because of abnormal hemoglobin.
Complete Answer:
The defect in the metabolism of the amino acid phenylalanine results in Phenylketonuria. Phenylketonuria PKU is an autosomal recessive disorder i.e. it is inherited from parents to children. This happens due to a mutation on chromosome 12 because of which the enzyme phenylalanine hydroxylase (PAH) is not produced in the body. This enzyme is responsible for converting phenylalanine into tyrosine and in its absence phenylalanine gets accumulated. This further gets converted into phenyl pyruvic acid which causes mental retardation.
Additional information: Let us look at the other disorders mentioned in the options.
Porphyria: It is a type of liver disorder in which a compound named porphyria gets accumulated in the body resulting in the deterioration of the skin and nervous system.
Wilson’s disease: It is a type of genetic disorder in which there is excess copper metal build up in the body which affects the functioning of the brain and the liver.
Tay Sach’s disease: It is also a genetic disorder that results in the destruction of nerve cells present in the brain and the spinal cord which results in the loss of the ability to sit, walk or even crawl.
So, the correct option is ‘(b) Phenylketonuria’.
Note:
- Phenyl pyruvic acid is excreted through the urine as well because of their poor absorption by the kidneys.
- Other autosomal recessive disorders include sickle cell anemia in which the RBC becomes sickle-shaped due to a mutation in the hemoglobin.
- Another autosomal recessive disorder is thalassemia which is also a blood disorder caused because of abnormal hemoglobin.
Recently Updated Pages
Algae are divided into three main classes What are class 11 biology CBSE

In the titration between oxalic acid and acidified class 11 chemistry CBSE

The pair of straight lines joining the origin to the class 11 maths CBSE

Find the speed of sound in a mixture of 1 mol of helium class 11 physics CBSE

The first excitation potential of a given atom is 102 class 11 physics CBSE

Name the substance which on treatment with chlorine class 11 chemistry CBSE

Trending doubts
10 examples of friction in our daily life

One Metric ton is equal to kg A 10000 B 1000 C 100 class 11 physics CBSE

Difference Between Prokaryotic Cells and Eukaryotic Cells

State and prove Bernoullis theorem class 11 physics CBSE

What organs are located on the left side of your body class 11 biology CBSE

How many valence electrons does nitrogen have class 11 chemistry CBSE
