Chromosomes and Mitosis

• What do most cells in your body contain?

  A nucleus
• What do chromosomes contain?

  Genetic material in the form of DNA
• What are chromosomes made of?

  Coiled up lengths of DNA molecules
• What do different genes on chromosomes control?

  The development of different characteristics
• How many copies of each chromosome do body cells normally have?

  Two copies
• Where do the two copies of chromosomes come from?

  One from the mother and one from the father
• How many pairs of chromosomes do humans have?

  23 pairs
• What is the purpose of the cell cycle in multicellular organisms?

  To produce new cells for growth and repair
• What is the stage of the cell cycle when the cell divides called?

  Mitosis
• How do multicellular organisms use mitosis?

  To grow or replace damaged cells
• What is the result of the cell cycle?

  Two new cells identical to the original
• What are the main stages of the cell cycle?

  • Growth & DNA Replication
  • Mitosis
• What happens to DNA in a cell that is not dividing?

  It is spread out in long strings
• What must a cell do before it divides?

  Grow and increase subcellular structures
• What happens to DNA before cell division?

  It duplicates to form X-shaped chromosomes
• What occurs during mitosis regarding chromosomes?

  They line up and are pulled apart
• What forms around the sets of chromosomes after mitosis?

  Membranes that become nuclei of new cells
• What happens to the cytoplasm and cell membrane after mitosis?

  They divide to form two new daughter cells
• What is true about the DNA in daughter cells after mitosis?

  It is identical to the parent cell's DNA
• What is the process of mitosis in simple terms?

  1. Chromosomes line up at the center
  2. Cell fibers pull them apart
  3. Membranes form around each set
  4. Cytoplasm and membrane divide
  5. Two identical daughter cells are formed
• If a student counts 11 cells undergoing mitosis out of 73 total cells, what is the percentage of cells undergoing mitosis?

  $15.07\%$
• How can a student tell if a cell is undergoing mitosis?

  By observing the alignment of chromosomes