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• Walther Flemming


  • First to observe chromosomes
  • Called it "chromatin"
  • Greek word "chroma" meaning "color"
  • Why? Due to its threadlike structure
  • Later called "chromosome" (soma = bodies, "colored bodies")
• Walter Stanborough Sutton & Theodor Heinrich Boveri

  • Chromosomal theory of inheritance
  • Inherited traits are controlled by genes located in chromosomes, transmitted to next generation through sex cells
• Genetics


  • Study of heredity
  • How genes are passed from one generation to another
• Gregor Johann Mendel


  • Father of Modern Genetics
  • Austrian monk
  • Law of dominance
  • Law of segregation
  • Law of independent assortment
• Allele


  One of the pair of genes located at the same position on both members of a pair
• Genotype


  • Genetic composition of the person
  • Represented by paired letters
• Phenotype


  Physical appearance of feature
• Dominant trait


  Dominates or masks another form of the same trait
• Recessive trait


  Appears least often in offspring
• Homozygote


  2 identical alleles for a trait
• Heterozygote


  2 different alleles for a trait
• Dominant Alleles


  • Loud and bossy
  • Capital letter
• Recessive Alleles


  • Very shy, super shy, super shy but wait a minute til I make u mine
  • Lower-case letter
• Law of Dominance


  • In heterozygous, only one of the two genes is physically expressed
  • "I'm more goated"
• Law of Segregation


  • Segregate during gamete formation
  • Separated genes are received by each gamete
• Law of independent assortment


  2 or more segregate/separate independently
• Parts of a Cell

  • Cytoplasm
  • Nucleus
  • Cell membrane
• Parts of a chromosome

  • Centromere
  • Telomere
  • Chromatid
• Cell Cycle


  1. Interphase: Longest phase

  2. G1 Phase: Cellular contents replicate, rapid growth and metabolic activity

  3. S Phase: Chromosomes duplicate, growth & DNA synthesis

  4. G2 Phase: Double checking, growth and preparation for final division
• Meiosis II


  Telophase II: 4 haploid daughter cells result from one original diploid cell
• Mitosis (PMAT)


  1. Prophase: Chromosomes condense & nuclear envelope breaks down

  2. Metaphase: Chromosomes line up along the metaphase plate

  3. Anaphase: Centromeres divide, pulled to each pole

  4. Telophase: Nuclear envelope forms around chromosomes
• Mitosis


  Cycle, diploid, somatic cells
• Meiosis


  Not a cycle, haploid, gamete cells
• Meiosis (Reduction Division)


  1. Prophase I: Synapsis occurs, chromosomes condense, nuclear membrane disappears

  2. Metaphase I: Tetrads move to the center, attach to spindle fibers from opposite centrioles

  3. Anaphase I: Homologous chromosomes pulled to opposite poles

  4. Telophase I: Daughter nuclei are formed, spindle fibers disappear, nuclear membrane reforms
• Homologous pair


  Identical, carry the same trait
• Synapsis


  Pairing of homologous chromosomes, forms a tetrad
• Crossing over


  Chromatids of tetrads exchange parts, produces genetic variety
• Alleles


  One of the pair of genes located at the same position on both members of a pair of chromosomes
• Mouth


  • Mechanical and chemical digestion take place
  • Teeth: Mechanically
  • Saliva: Chemically, contains amylase which helps break down starch
• Different organs in the digestive system

  • Esophagus
  • Stomach
  • Small Intestine
  • Large Intestine
  • Rectum
  • Accessory organs (Salivary glands, liver, pancreas)
• Esophagus


  Approx. 20 cm long, secretes mucus, connects pharynx to stomach, moves food using peristalsis
• Stomach


  Mixes food with digestive juices to break down proteins and lipids, food leaves as chyme
• Small Intestine


  7m long, villi and microvilli increase surface area for absorption
• Large Intestine


  1.5m long, accepts what small intestines don't absorb, absorbs more water and concentrates wastes
• Rectum


  Short term storage which holds feces
• Accessory organs


  • Salivary glands
  • Liver
  • Pancreas
• Salivary Glands


  • 6 glands (2 submaxillary, 2 parotid, 2 sublingual)
  • Secrete saliva containing amylase/ptyalin which changes starch into maltose
• Liver


  Largest gland in the body, produces bile, filters out toxins and waste
• Bile


  Yellow green liquid, helps digest fat, filters out toxins and waste
• Gallbladder


  Stores bile from the liver, releases it into the small intestine