Question
An example of a chromosomal mutation is shown. What is the most likely cause of this type of mutation? A DNA segment was inserted into a non-homologous chromosome. A tip of one chromosome was transferred to another chromosome. Chromosomes failed to separate properly during meiosis II. An extra copy of the chromosome was produced during replication. 4 of 4 QUESTIONS
Answer
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Oswald
Expert · Tutor for 3 years
Answer
Based on the given options, the most likely cause of a chromosomal mutation is option 3: "Chromosomes failed to separate properly during meiosis II". This process, known as nondisjunction, can result in daughter cells with an abnormal number of chromosomes, leading to a variety of genetic disorders.
Explanation
Chromosomal mutations are changes that occur in the structure or number of whole chromosomes or parts of chromosomes. These mutations can be caused by several factors, including errors in DNA replication, exposure to radiation or chemicals, or problems during meiosis.## Step 1:Analyzing the first option: "A DNA segment was inserted into a non-homologous chromosome". This describes a type of chromosomal mutation called translocation, where a segment of DNA is moved from one chromosome to another. This can cause a mutation if the inserted segment disrupts the function of genes on the receiving chromosome.## Step 2:Analyzing the second option: "A tip of one chromosome was transferred to another chromosome". This also describes a type of translocation, specifically a reciprocal translocation, where segments from two different chromosomes have been swapped. This can disrupt the function of genes at the breakpoints.## Step 3:Analyzing the third option: "Chromosomes failed to separate properly during meiosis II". This describes a process called nondisjunction, which can result in aneuploidy - an abnormal number of chromosomes in the daughter cells. This can cause conditions such as Down syndrome, which is caused by an extra copy of chromosome 21.## Step 4:Analyzing the fourth option: "An extra copy of the chromosome was produced during replication". This describes a process called chromosome duplication, where a chromosome or a part of a chromosome is duplicated. This can result in an increase in the number of copies of the genes on that chromosome, which can disrupt the normal function of those genes.