What are chromatids?

• A. Duplicate halves of a chromosome
• B. Protein complexes on the centromere that allows for cell division
• C. A minute cylindrical organelle near the nucleus in animal cells
• D. DNA molecules that are tightly coiled around histones

Answer: (A)

Chromatids are the duplicated halves of a chromosome created during DNA replication. After replication, each chromosome consists of two identical sister chromatids that remain attached at the centromere. They carry exact copies of the genetic information and are pulled apart during cell division to form separate chromosomes in the daughter cells. The other options describe different cellular structures or concepts: protein complexes at the centromere that help with spindle attachment are kinetochores, a small cylindrical organelle near the nucleus refers to centrioles, and DNA tightly coiled around histones describes chromatin packaging rather than the duplicated halves of a chromosome.