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प्रश्न
What is point mutation? Give one example.
उत्तर
When heritable changes occur in a very short region of the DNA molecule, such as a single nucleotide or nucleotide pair, these are referred to as point mutations. Point mutations can be caused by inversion, substitution (transition and transversion), or frameshift (insertion and deletion) nucleotide changes in DNA or RNA. Phenylketonuria (PKU; Polling 1934) is an inborn, autosomal, recessive metabolic condition in which the homozygous recessive individual lacks the enzyme phenylalanine hydroxylase, which is required to convert phenylalanine (amino acid) to tyrosine (amino acid) in the liver. It causes hyperphenylalaninemia, which is marked by the accumulation and excretion of phenylalanine, phenylpyruvic acid, and other substances. The enzyme lack is caused by a defective autosomal recessive gene on chromosome 12. This gene is faulty as a result of replacement. Affected child are OK at birth, but within a few weeks, plasma phenylalanine levels spike (30-50 times), impairing brain development. Other signs include mental impairment, reduced pigmentation in the hair and skin, and eczema.
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संबंधित प्रश्न
Answer the following question.
Two children, A and B aged 4 and 5 years respectively visited a hospital with a similar genetic disorder. The girl A was provided enzyme-replacement therapy and was advised to revisit periodically for further treatment. The girl, B was, however, given a therapy that did not require revisit for further treatment.
Name the ailments the two girls were suffering from?
Answer the following question.
Two children, A and B aged 4 and 5 years respectively visited a hospital with a similar genetic disorder. The girl A was provided enzyme-replacement therapy and was advised to revisit periodically for further treatment. The girl, B was, however, given a therapy that did not require revisit for further treatment.
How was the girl B cured permanently?
Match List I with List II.
| List I | List II | ||
| A. | A pair of chromosomes extra with diploid | i) | monosomy |
| B. | One chromosome extra to the diploid | ii) | tetrasomy |
| C. | One chromosome loses from diploid | iii) | trisomy |
| D. | Two individual chromosomes lose from diploid | iv) | double monosomy |
What is the difference between missense and nonsense mutation?
Draw the diagram of different types of aneuploidy.
One of the parents of a cross has mutation in its mitochondria. In that cross, that parent is taken as a male. During segregation of F2 progenies that mutation is found in ______.
A change of single base pair in the gene for beta-globin chain (in human haemoglobin) results in the change of amino acid residue glutamic acid to valine which is due to ______
A strong mutagen is:
How are alleles of particular gene differ from each other? Explain its significance.
How does a mutagen induce mutation? Explain with example.
Match list I with list II.
| List I | List II | ||
| A. | A pair of chromosomes extra with diploid | (i) | monosomy |
| B. | One chromosome extra to the diploid | (ii) | tetrasomy |
| C. | One chromosome loses from diploid | (iii) | trisomy |
| D. | Two individual chromosomes lose from diploid | (iv) | double monosomy |
Match list I with list II.
| List I | List II |
| A. A pair of chromosomes extra with diploid | i) Monosomy |
| B. One chromosome extra to the diploid | ii) Tetrasomy |
| C. One chromosome loses a diploid | iii) Trisomy |
| D. Two individual chromosomes lose their diploid | iv) Double chromosome |
Match list I with list II.
| List I | List II | ||
| A. | A pair of chromosomes extra with diploid | i) | monosomy |
| B. | One chromosome extra to the diploid | ii) | tetrasomy |
| C. | One chromosome loses from diploid | iii) | trisomy |
| D. | Two individual chromosomes lose from diploid | iv) | double monosomy |
Match list I with list II.
| List I | List II | ||
| A. | A pair of chromosomes extra with diploid | i) | monosomy |
| B. | One chromosome extra to the diploid | ii) | tetrasomy |
| C. | One chromosome loses from diploid | iii) | trisomy |
| D. | Two individual chromosomes lose from diploid | iv) | double monosomy |
Match list I with list II
| List I | List II | ||
| A. | A pair of chromosomes extra with diploid | i) | monosomy |
| B. | One chromosome extra to the diploid | ii) | tetrasomy |
| C. | One chromosome loses from diploid | iii) | trisomy |
| D. | Two individual chromosomes lose from diploid | iv) | double monosomy |
