Genetics Lab

• Animal cell


  An irregularly shaped, eukaryotic, or nucleus-containing, cell with a flexible membrane
• Animal cell


  • Does not have a cell wall
  • Can take on various shapes
• Parts of animal cell

  • Nucleus
  • Cytosol
  • Golgi apparatus
  • Lysosome
  • Cell membrane
  • Centrosome
  • Endoplasmic reticulum
  • Ribosome
  • Vacuole
  • Mitochondrion
• Animal cells range between 10 to 30 micrometers in size, smaller than the diameter of human hair
• Animal cells are different from other cells because they do not have a cell wall, which allows them to take on various shapes
• With this flexibility, animal cells have evolved and diversified into the animal kingdom we know today
• Nucleus


  Contains DNA, the genetic blueprint of a living organism
• Cytosol


  Fluid within the cell that surrounds the organelles
• Golgi apparatus


  Membrane-bound sac responsible for producing, storing, and transporting proteins and lipids
• Lysosome


  An organelle that contains digestive enzymes and breaks down biological molecules
• Cell membrane


  Two layers of lipid, or fat, molecules that enclose the cell and regulate which molecules can go inside and outside of the cell
• Centrosome


  Organelle near the nucleus that helps with the production of microtubules
• Endoplasmic reticulum


  Network of membranes that helps synthesize proteins and lipids
• Ribosome


  Small organelle often attached to the endoplasmic reticulum that helps create proteins
• Vacuole


  Fluid-filled organelle that stores food and nutrients
• Mitochondrion


  A bean-shaped organelle responsible for converting raw materials into usable energy
• Dandruff is a common condition that causes the skin on the scalp to flake
• Causes of dandruff


  • Irritated, oily skin
  • Dry skin
  • A yeastlike fungus (Malassezia) that feeds on oil on the scalp
  • Sensitivity to hair care products (contact dermatitis)
  • Other skin conditions, such as psoriasis and eczema
• Masturbation is considered the preferred way to get a clean sperm sample
• Good sperm sample


  • Semen must be kept at body temperature
  • Examine the sample within 30 to 60 minutes of leaving the body
• The nucleus houses the genetic material (DNA), which directs all the cell activities
• Nucleoplasm


  Fluid which the following are suspended: Nucleolus, Chromatin
• Nucleolus


  Composed largely of RNA and protein – where ribosomes are formed
• Chromatin


  Loosely coiled fibers of DNA – info for protein synthesis
• Chromosomes


  When the cell begins to divide, chromatin coil tightly into to become chromosomes
• Chromatids


  2 identical "sister" chromatids attached at an area in the middle called a centromere
• Cell cycle


  The series of changes a cell undergoes from the time it forms until it divides
• Phases of cell cycle

  • Interphase (Preparation - cell grows and duplicates its contents)
  • Cell division (Mitosis - Increase cell number, Cytokinesis - division of the cytoplasm)
  • Cell differentiation - cell specialization into different types of cells
• Mitosis


  1. Prophase

  2. Metaphase

  3. Anaphase

  4. Telophase
• Meiosis


  • Occurs during gametogenesis – formation of the egg cells and sperm cells
  • Have half (n) number of chromosomes: 23
  • Reduction division
• DNA Extraction


  The isolation and purification of DNA
• Extracting DNA in 10 Easy Steps

  1. Mush the banana

  2. Fill a cup with the hot water and salt

  3. Pour the saltwater mix into the bag

  4. Add the dishwashing soap

  5. Place the coffee filter in a clear glass cup

  6. Pour the mix into the filter

  7. Remove and discard the used coffee filter

  8. Tilt the glass and slowly add cold alcohol

  9. Wait for eight minutes

  10. Use the wooden stirrer to start poking the cloudy stuff in the alcohol layer
• Saltwater


  Helps the DNA strands to stick to each other in clumps large enough for you to see
• Dish soap


  Can help split apart the membranes (the outer "skin") that holds cells together
• Alcohol


  The DNA clumps are soluble (can be dissolved) in some liquids, but not in alcohol. So adding alcohol helps the clumps of DNA to form
• DNA Extraction Principle


  Involves lysis of cellular and nuclear membranes in order to extract DNA from within, followed by DNA separation from impurities, proteins, and other substances
• General Stages of DNA Extraction

  • Cell dissolution: lysis of cell and the nucleus to extract DNA into the buffer
  • Precipitation: removing the impurities and proteins from the sample
  • Purification: to get a completely pure DNA sample ready to be used
• Chemical-based DNA extraction method

  • Organic solvent-based
  • Inorganic solvent-based
  • Proteinase K
  • Salting out method
  • SDS (sodium dodecyl sulfate)
  • CTAB
  • Silica-gel based techniques
• Physical or Solid-Based Methods

  • Paper DNA extraction
  • Magnetic bead DNA extraction
• Purpose of DNA extraction

  To obtain DNA in a relatively purified from which can be used for further investigations such as: PCR, RFLP, Southern blotting