Which term describes a form of asexual reproduction in single-celled organisms where one cell divides into two cells of the same size?

• A. External fertilization
• B. Binary fission
• C. Mutualism
• D. Mimicry

Answer: (B)

Binary fission is a form of asexual reproduction used by many single-celled organisms. In this process, the cell duplicates its genetic material, grows, and then splits down the middle to form two daughter cells of equal size. No mating or exchange of genetic material occurs, so the offspring are genetically identical to the parent (aside from occasional mutations). This is common in prokaryotes like bacteria and in some single-celled eukaryotes. External fertilization requires gametes from two organisms and is sexual reproduction; mutualism is a type of ecological interaction; mimicry is an adaptation for defense or deception.