Structure of chromosomes in mitosis

• At the beginning the chromosomes are made of two strands joined in the middle by a centromere
• Separate strands of a chromosome are called chromatids
• Two strands on the same chromosome are called sister chromatids
• There are two strands as each chromosome has made an identical copy of itself during interphase
• After mitosis the chromatids end up as one-strand chromosomes in the new daughter cells
• Diagram

  A) Centromere

  B) One chromatid

  C) Sister chromatids