Which of the following is an example of a safe haven for transposon movement?

• A. Intron
• B. Exon
• C. Promoter
• D. Enhancer

Answer: (A)

Verified step by step guidance

1. Understand the concept of transposons: Transposons, also known as 'jumping genes', are DNA sequences that can change their position within the genome. This movement can disrupt or modify genes and regulatory regions.
2. Identify what a 'safe haven' means in the context of transposon movement: A 'safe haven' is a region in the genome where the insertion of a transposon is less likely to disrupt essential genetic functions.
3. Consider the role of introns: Introns are non-coding regions within a gene that are removed during RNA splicing. Since they do not code for proteins, insertions here are less likely to disrupt gene function, making them a potential 'safe haven'.
4. Evaluate the other options: Exons are coding regions that directly affect protein synthesis, so transposon insertion here can be disruptive. Promoters and enhancers are regulatory regions crucial for gene expression, and their disruption can have significant effects.
5. Conclude that introns, being non-coding and less likely to affect gene function when disrupted, serve as a 'safe haven' for transposon movement compared to exons, promoters, and enhancers.