MITOSIS and CELL CYCLE CHECKPOINTS

• Apoptosis: programmed cell death
• cell division benefits:

  1. growth
  2. development
  3. maintaining health
  4. healing from diseases or injury
• cytokinesis: the division of the cytoplasm into two daughter cells
• Apoptosis: tightly regulated process
• Importance of apoptosis:

  1. Embryonic development
• Embryonic development: shapes the structures in the body
• Embryonic development: removes unnecessary improperly formed cells
• importance of apoptosis:

  2. tissue remodeling
• importance of apoptosis:

  3. immune system
• importance of apoptosis:

  4. hormone - it induce cell death
• Mitosis: cell division of DNA and cells
• Cell Cycle: series of events that takes place in a cell as it grows and divide
• True or False:

  rate depends in different tissues at the different times
• Neurons: amitotic, irreplaceable
• G2 Phase: Gap 2 phase, where the cell prepares for mitotic division by completing any remaining protein synthesis and organelle duplication.
• Skin Cells: mitotic, replaceable
• G1 Phase: growth phase (cell increases in size)
• Stem Cell: undifferentiated, can be replaced by other stem cells
• Prophase: chromatin condenses into visible chromosomes, nuclear envelope breaks down, centrioles move to opposite poles, spindle fibers form between them
• Metaphase: chromosomes line up along equatorial plane of cell, attached to spindle fibers
• Anaphase: sister chromatids separate from one another, pulled apart by spindle fibers towards opposite ends of cell
• M Phase: Mitosis phase, where the chromosomes are separated into two daughter cells.
• Interphase: The longest stage of the cell cycle, during which the cell grows and replicates its genetic material (DNA). It is divided into three sub-phases: G1, S, and G2.
• Prokaryotes: single-celled microorganisms without nuclei, such as bacteria.
• Anaphase: sister chromatids separate from each other and are pulled towards opposite ends of the cell by spindle fibers
• Mitosis is the process of cell division that results in two genetically identical daughter cells from one parent cell.
• Telophase: new nuclei form at each end of the cell, chromosomes uncoil back into chromatin, nuclear envelopes reform around each set of chromosomes, cytokinesis begins
• The stages of mitosis are prophase, metaphase, anaphase, telophase, and cytokinesis.
• Cancerous Cells: abnormal, cannot be replaced by normal cells
• G0: non-divides state, serves as decision point
• S phase: DNA replication, DNA is copied and chromosomes are duplicated, enzymes, DNA polymerase
• Prophase: short and thick of chromosomes
• Control of the Cell Cycle: regulatory mechanisms
• Cell Cycle Checkpoint: maintain genetic stability
• Cell Cycle Checkpoint: groups of intercalating proteins
• Cell Cycle Checkpoint ensure that chromosomes are correctly replicated and apportioned into daughter cells
• Cyclin-dependent kinases (CDKS) - occurs at specific time and phase
• p53 - a tumour suppressor gene (TP53 GENE) that is mutated in many cancers and becomes protein
• Cell Growth Checkpoint - known as Restriction Checkpoint
• Cell Growth Checkpoint - occurs at the end of G1.