What is the difference between a chromatid and a chromosome? a. Chromatids consist of DNA, whereas chromosomes consist of proteins. b. A chromatid is one half of a replicated chromosome, whereas a chromosome consists of DNA wrapped around proteins in a highly organized manner. c . Chromosomes are always replicated, whereas chromatids are not. d. A chromatid always consists of two linear DNA molecules, whereas a chromosome always consists of just one linear DNA molecule.