Which of the following occurs in binary fission but not in mitosis with cytokinesis?

• A. Cytokinesis involving a cleavage furrow
• B. Separation of sister chromatids
• C. Replication of a single circular DNA molecule
• D. Formation of a mitotic spindle

Answer: (C)

Verified step by step guidance

1. Understand the process of binary fission: Binary fission is a method of asexual reproduction commonly found in prokaryotes, such as bacteria. It involves the replication of the organism's single, circular DNA molecule and the division of the cell into two genetically identical daughter cells.
2. Compare binary fission with mitosis: Mitosis is a process of cell division in eukaryotic cells that involves the separation of sister chromatids and the formation of a mitotic spindle. It is usually followed by cytokinesis, which divides the cytoplasm of the parent cell into two daughter cells.
3. Identify the unique feature of binary fission: In binary fission, the replication of a single circular DNA molecule occurs, which is distinct from the processes involved in mitosis. Eukaryotic cells undergoing mitosis have multiple linear chromosomes, not a single circular DNA molecule.
4. Recognize the role of cytokinesis: In mitosis, cytokinesis often involves the formation of a cleavage furrow in animal cells, which is not a feature of binary fission. Binary fission does not involve a mitotic spindle or the separation of sister chromatids, as seen in mitosis.
5. Conclude the distinguishing factor: The replication of a single circular DNA molecule is a key event in binary fission that does not occur in mitosis with cytokinesis, making it the correct answer to the problem.