meiosis

• What are proteins that regulate the timing of the cell cycle in eukaryotic cells called?

  Cyclins
• What do cyclins do when introduced to a cell?

  They cause mitotic spindles to form
• What types of regulators are there for cell division?

  There are both internal and external regulators
• What can a mutation in a cell's DNA create?

  Cancer cells that do not respond to growth signals
• What is the result of some cancer cells failing to respond to external regulators?

  They continue to grow uncontrollably
• What is the purpose of meiosis?

  To reduce the number of chromosomes in new cells to half
• What type of cells does meiosis usually produce?

  Haploid cells called gametes
• What does the condensing of chromosomes allow for?

  Easy movement of a large amount of information
• How many chromosomes do humans have in each body cell?

  46 chromosomes or 23 pairs
• What is the chromosome condition of a normal human body cell?

  Diploid
• How many chromosomes do human gametes have?

  23 chromosomes
• What are sex chromosomes responsible for?

  Determining the sex of the organism
• What are the sex chromosomes for females and males?

  XX for females and XY for males
• What are all other chromosomes besides sex chromosomes called?

  Autosomes
• What are homologous chromosomes?

  A pair of autosomes that go together
• What does independent assortment refer to in meiosis?

  The random separation of chromosomes producing unique genetic combinations
• What happens during crossing over in meiosis?

  Chromosome arms can become tangled and exchange places
• What occurs during Meiosis I?

  The original cell produces two new cells with half the number of chromosomes
• How many chromosomes does each new cell have after Meiosis I?

  Each new cell has one chromosome from the homologous pair
• What is the result of Meiosis II?

  A cell with half as many chromosomes as the original
• What are the stages of Meiosis I?

  • Prophase I
  • Metaphase I
  • Anaphase I
  • Telophase I
• What are the stages of Meiosis II?

  • Similar to Mitosis
  • Results in cells with half the number of chromosomes
• What is chemotherapy used for?

  To treat cancer
• What is the main difference between mitosis and meiosis?

  Mitosis produces identical cells, while meiosis produces genetically diverse cells