Cell Cycle and Cancer

Cards (44)

  • Cells need to divide to replace damaged cells or cells at the end of their life span.
  • Cells need to divide to reproduce asexually to make genetic identical copies.
  • Cells need to divide to grow tissues and organs in young organisms.
  • Chromosomes are fancily packed DNA.
  • In prokaryotic cells, DNA is packaged into a single, circular chromosome.
  • In eukaryotic cells, DNA is packaged into multiple chromosomes.
  • Humans have 46 chromosomes.
  • Prokaryotes undergo binary fission once reached a certain size.
  • Binary Fission: type of division that only prokaryotic cells do.
  • In prokaryotes, the DNA duplicates, then the cell membrane indents before the cell divides into two new cells.
  • Eukaryotic cells have a more complex cell cycle than prokaryotic cells.
  • G1 phase involves cell growth.
  • S phase involves DNA replication.
  • G2 phase involves preparation for mitosis.
  • The cell division stage, or M phase, has mitosis and cytokinesis.
  • Internal regulators respond to events inside the cell.
  • Internal regulators let the cell cycle process only when certain steps have already happened.
  • External regulators respond to events outside the cell.
  • External regulators direct cells to speed or slow down the cell cycle.
  • Growth Factors: wound healing and embryonic development.
  • In 9 months, one cell becomes millions of cells.
  • Cells grow quickly during birth & puberty.
  • During wound healing, growth factors turn on at the end of the wound.
  • Cells at the edge of an injury are stimulated to divide rapidly.
  • As the injury heals, the rate of cell division slows as the body heals and repairs itself.
  • Cyclins: proteins that regulate the cell cycle.
  • Apoptosis removes extra cells during development and wound healing and maintain structure.
  • Apoptosis is programmed cell death. It has an important role in structuring tissues during growth and development.
  • During apoptosis, the cell undergoes a series of controlled steps for self-destruction.
  • Genetic changes can cause cancer as they lead to abnormal growth resulting in masses of tissues called tumors.
  • Proto-oncogene: signals a cell to grow & divide.
  • Tumor Suppressor Genes: signals a cell to stop dividing.
  • DNA Repair Genes: preserve & maintain genetic codes.
  • There are two types of tumors.
  • Benign tumors remain in one place.
  • Malignant tumors are able to spread.
  • Through metastasis, malignant tumor cells will break off, travel through the body, and form tumors in other regions.
  • Cancer cells do not respond to normal regulatory signals.
  • The cell cycle is disrupted due to uncontrolled cell growth. Cells grow and divide uncontrollably.
  • Cancer results from a defect in genes that control cell growth & division.