Science All

• Mitosis


  How a cell divides to produce 2 new identical daughter cells
• Mitosis


  • Only occurs in somatic (body) cells
  • Purpose is for growth and development
  • Replaces worn-out tissue
• Body cell examples


  • Red blood cells
  • White blood cells
  • Bone
  • Nerve
  • Liver
  • Skin
  • Muscle cells
• Cell division checkpoint


  Cell will only begin mitosis if conditions are correct and favorable (G2 to M checkpoint)
• Mitosis process


  1. Prophase

  2. Pro-Metaphase

  3. Metaphase

  4. Anaphase

  5. Telophase
• Mitosis


  Also known as EQUATIONAL DIVISION
• 1. Phase


  Meiosis - sex cells (gametes)<|>Mitosis - body cells (somatic)
• Cell division


  Allows cell to divide and produce new cells
• Haploid


  Meiosis
• Diploid


  Mitosis
• Chromatin


  DNA in interphase is found in the form of chromatin which condenses during mitosis
• Chromosome


  Each chromosome is made up of 2 sister chromatids
• Chromosome


  • Short and thick
• Parts of a chromosome

  • Centromere
  • Kinetochore
  • Telomere
  • Chromosome arm (p-arm and q-arm)
• Centromere


  Attaches 2 sister chromatids<|>Attachment point for microtubules
• Kinetochore


  Region where spindle fiber is attached to (protein complex)
• Telomere


  Ends of linear chromosome, protection for internal region, identifies our human age (not yet proven), stabilize
• Chromosome arm


  1. arm (short; upper part)<|>q-arm (long; lower part)
• Types of chromosomes


  • Metacentric
  • Submetacentric
  • Acrocentric
  • Telocentric
• Metacentric chromosome


  Two arms are equal
• Submetacentric chromosome


  One arm is somewhat shorter
• Acrocentric chromosome


  One arm is much shorter
• Telocentric chromosome


  Each has only 1 arm, centromere is at one end of the chromosome
• Human genome


  23 pairs of chromosomes for a total of 46 chromosomes in each cell
• Haploid


  One set of chromosomes
• Diploid


  Two sets of chromosomes (represented as 2n: 46)
• Spindle fiber came from centrioles
• Chromosome activities during mitosis

  1. Become visible to the microscope

  2. Nuclear envelope disintegrates and interlay disappear

  3. Formation of spindle fiber
• • begins after nuclear envelope disintegrates
  • centrosomes moves to the opposite pole


  Pro-Metaphase
• Who proposed Continental Drift Theory?

  Alfred Wegener
• 2 Principle of Mendel's Law

  1. Principle of Segregation
  2. Principle of Independent Assortment
• Augustinian monk who cross-bred pea plants with different characteristics


  Gregor Mendel
• The removal of sediments from their source area

  Erosion
• The downslope movement of sediments by gravity.


  Mass Wasting
• rocks that cover 90% of Earth’s surface


  Sedimentary Rocks
• These rocks cool rapidly on or very near the Earth’s surface.

  Extrusive Igneous Rocks
• These rocks cool slowly within the Earth’s crust.

  Intrusive Igneous Rocks
• three major geological settings:

  (1) mid-ocean ridges, (2) subduction zones, and

  (3) hotspots.
• form by solidification of a cooling magma (molten rock).

  Igneous Rocks
• form by transformation of the chemical and/or mineralogical composition and/or texture of a preexisting rock in a solid state due to changing conditions of temperature and/or pressure or due to interactions with hydrothermal fluids.

  Metamorphic Rocks