Which statement is true regarding chromosome replication in eukaryotes?

• A. Eukaryotic chromosomes replicate entirely in the cytoplasm.
• B. Each chromosome is replicated only once every cell cycle, but at random times.
• C. Replication occurs at multiple origins along the chromosome.
• D. Replication proceeds in a unidirectional manner from a single origin.

Answer: (C)

Verified step by step guidance

1. Understand that eukaryotic chromosomes are linear and contain multiple origins of replication. This is different from prokaryotic chromosomes, which typically have a single origin of replication.
2. Recognize that replication in eukaryotes occurs in the nucleus, not the cytoplasm. This is because eukaryotic cells have a defined nucleus where the DNA is housed.
3. Learn that each chromosome is replicated once per cell cycle during the S phase, ensuring that the entire genome is duplicated before cell division.
4. Know that replication proceeds bidirectionally from each origin. This means that replication forks move outward in both directions from the origin, allowing for efficient replication of large eukaryotic chromosomes.
5. Identify that multiple origins of replication are necessary to complete the replication of large eukaryotic chromosomes in a timely manner during the S phase of the cell cycle.