To determine whether the scientist's claim about genetic variation occurring during meiosis is correct, we need to analyze the definitions of the processes mentioned in each option.
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Nondisjunction refers to the failure of homologous chromosomes or sister chromatids to separate properly during cell division, leading to gametes with an abnormal number of chromosomes. This can result in genetic variation due to the creation of gametes that carry different numbers of chromosomes than typical, which can lead to conditions such as Down syndrome or Turner's syndrome.
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Deletion mutation involves the loss of nucleotides from a DNA sequence. This typically occurs at the level of the DNA sequence rather than the chromosome number and does not directly relate to meiosis in the same way that nondisjunction does.
Now, let’s analyze the answer choices:
- (a) The scientist is incorrect. The process shown is a deletion mutation, which does not create genetic variation during meiosis.
- (b) The scientist is incorrect. The process shown is nondisjunction, which actually causes genetic variation due to abnormal chromosome numbers.
- (c) The scientist is correct. The process shown is nondisjunction, and it does result in an incorrect amount of genetic information, leading to genetic variation.
- (d) The scientist is correct. The process shown is a deletion mutation, which causes genetic variation, but it does not specifically say it is related to meiosis.
Given the options and understanding the concepts of nondisjunction and deletion mutations, the most accurate answer is:
(c) The scientist is correct. The process shown in the diagram is nondisjunction, in which chromosomes fail to separate normally, causing an incorrect amount of genetic information to be inherited.
1 answer