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• Mitosis

  A type of cell division in which the nucleus of the cell divides into 2 nuclei with identical genetic material
• Mitosis

  • Resulting in 2 diploid (2n) daughter cells after division of a diploid (2n) parent cell containing two sets of chromosomes
  • Human body cell contains 46 chromosomes
  • Occurs only in eukaryotes and used by multicellular organisms for growth, development, repair, and asexual reproduction
• Stages of Mitosis

  1. Prophase

  2. Metaphase

  3. Anaphase

  4. Telophase

  5. Cytokinesis
• Prophase

  1. Chromatids coil and become visible

  2. Each chromosome contains 2 identical sister chromatids

  3. Nuclear membrane dissolves and spindle fibers form

  4. Centrioles migrate to opposite poles and nucleolus disappears
• Metaphase

  1. Chromosomes align at the metaphase plate

  2. Spindle fibers connect each chromosome to the centrioles at opposite poles
• Anaphase

  1. Proteins binding sister chromatids divide

  2. Separated chromosomes move to opposite poles due to shortening of spindle fibers
• Telophase

  1. Nuclear membrane reforms around chromosomes which start to uncoil

  2. Spindle fibers dissolve

  3. Each chromosome in daughter cell is one chromatid

  4. Cytokinesis begins
• Cytokinesis

  1. In animal cells, cleavage furrow forms at exterior and moves inward

  2. In plant cells, cell plate forms at middle and moves outward
• Meiosis

  A type of cell division used by multicellular organisms to form reproductive cells (gametes) with half the number of chromosomes
• Meiosis

  • Produces 4 haploid (n) daughter cells from 1 diploid (2n) parent cell
  • Meiosis I is a reductional division, Meiosis II is an equational division
• Stages of Meiosis

  1. Prophase I

  2. Metaphase I

  3. Anaphase I

  4. Prophase II

  5. Metaphase II

  6. Anaphase II

  7. Telophase II
• Prophase I

  1. Chromosomes coil and shorten

  2. Nuclear envelope disintegrates

  3. Homologous chromosomes pair by synapsis

  4. Crossing-over may occur
• Metaphase I

  1. Paired homologous chromosomes align at metaphase plate

  2. Chromosomes attached to spindle fibers
• Anaphase I

  Homologous chromosomes separate and move to opposite poles
• Prophase II

  1. Nuclear membrane disintegrates

  2. New spindle fibers form
• Metaphase II

  Chromosomes align at metaphase plate, attached to spindle fibers at centromeres
• Anaphase II

  Each chromosome divides into sister chromatids which move to opposite poles
• Telophase II

  1. Nuclear membrane reforms around each set of chromosomes

  2. Spindle fibers disintegrate

  3. Cytokinesis occurs
• Stages of Cell Cycle

  • Interphase (G1, S, G2)
  • Mitosis (Prophase, Metaphase, Anaphase, Telophase, Cytokinesis)
• Gregor Johann Mendel

  Austrian monk, biologist, meteorologist, and mathematician known as the "Father of Modern Genetics"
• Mendel studied the pattern of inheritance using the garden pea Pisum sativum and experimented on almost 30,000 pea plants
• Reason Mendel chose pea plants

  They were easily grown and raised in the monastery garden, and each plant has both male and female sexual organs
• 7 contrasting traits Mendel studied in pea plants

  • Seed form (round/wrinkled)
  • Seed color (yellow/green)
  • Pod form (inflated/constricted)
  • Pod color (green/yellow)
  • Flower color (purple/white)
  • Flower position (axial/terminal)
  • Stem length (tall/short)
• Genetic Terminology

  • Alleles - alternative forms of a gene
  • Chromosome - linear or circular DNA strand containing genes
  • Diploid - organism with two copies of each chromosome
  • DNA - Deoxyribonucleic acid, the molecule that carries genetic information
  • Gene - the fundamental unit of heredity, a specific section of DNA