Which statement best explains why zebrafish experience similar genetic diseases as humans?

• A. Zebrafish and humans both reproduce asexually, leading to similar genetic outcomes.
• B. Zebrafish and humans share many homologous genes, so mutations can affect similar biological pathways.
• C. Zebrafish have identical chromosomes to humans, resulting in the same genetic diseases.
• D. Zebrafish are exposed to the same environmental factors as humans, causing the same diseases.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the concept of homologous genes. Homologous genes are genes in different species that evolved from a common ancestral gene and often retain similar functions.
2. Step 2: Recognize that zebrafish and humans share many homologous genes, meaning that many genes in zebrafish have counterparts in humans that perform similar biological roles.
3. Step 3: Realize that mutations in these homologous genes can disrupt similar biological pathways in both zebrafish and humans, leading to comparable genetic diseases.
4. Step 4: Evaluate the incorrect options: zebrafish and humans do not reproduce asexually, their chromosomes are not identical, and while environmental factors can influence disease, genetic similarity is the key reason for shared genetic diseases.
5. Step 5: Conclude that the best explanation is the shared homologous genes causing mutations to affect similar biological pathways, which explains why zebrafish experience genetic diseases similar to humans.