Biology eoc facts

• Experiments must be FAIR

  • Test one variable at a time
  • Repeat the experiment several times without changing the procedures
  • Have a control group that receives no treatment so you have something to compare your test with
  • Control as many factors as you can that might interfere with your results
  • Include many items in the experiment. Example: 30 plants and not 2, 100 people, not 10
• Scientific Method


  1. Title

  2. Hypothesis

  3. Materials

  4. Procedure

  5. Results

  6. Conclusion
• Water is polar; it has oppositely charged regions that allow soluble substances to be pulled apart (dissolved). Sugar is polar, oil is not.
• Carbohydrates


  • Monosaccharides (glucose, fructose)
  • Polysaccharides (starch, glycogen, cellulose)
• Monosaccharides


  Simple sugars C6H12O6; Glucose is blood sugar and is made by plants during photosynthesis
• Polysaccharides


  Complex chains of glucose
• Benedict's solution turns orange in the presence of sugars
• Iodine turns black in the presence of starch
• Lipids


  Stored energy, make up cell membrane, insulation fats and oils
• A brown paper bag becomes transparent in the presence of lipids
• Proteins


  Build body mass, muscle
• Biuret's solution turns purple in the presence of proteins
• Enzymes


  • Have a specific shape to fit with a substrate
  • Are reusable
  • Can be deactivated or denatured with extreme heat or cold
  • Most prefer neutral pH- 7 – and body temperature – 37 °C
• pH


  • Acids have more H+, bases have more OH-, neutral has equal amounts
  • Scale goes from 0-14, acid is less than 7 and base is more than 7
  • A weak acid is a 6, a strong acid is a 1, strong base is a 14
• Cell Membrane


  • Lipid bilayer – phospholipids and proteins
  • Selectively permeable: allows only certain substances in and out
• Diffusion


  Movement of particles from an area of high concentration to an area of low concentration
• Osmosis


  Diffusion of water
• Osmotic conditions


  • Isotonic – dynamic equilibrium – equal movement
  • Hypertonic – water will flow out of the cell to balance its environment
  • Hypotonic – water will flow in the cell to reach a balance
• Facilitated Diffusion


  Passive transport, no energy needed, for "fat" molecules that must go through protein channels
• Active Transport


  Energy is required – movement of particles from LOW to HIGH concentration
• Endocytosis


  Large particles surrounded and engulfed
• Exocytosis


  Large waste is expelled through the membrane
• Cell Theory – cells are the basic unit of life, cells come form other cells
• Cell parts


  • Cell Membrane
  • Cell Wall
  • Nucleus
  • Ribosomes
  • Mitochondria
  • Chloroplast
• Respiration


  1. Occurs primarily in the mitochondria

  2. Involves the breaking down of glucose in the presence of oxygen (aerobic)

  3. Products are Carbon dioxide, Water and ATP (energy)
• Photosynthesis


  1. Occurs in the chloroplasts

  2. Involves a reaction in which carbon dioxide and water combine in the presence of light energy to form glucose and release oxygen

  3. Light reaction – light is absorbed and converted to ATP, water is split, releasing oxygen

  4. Calvin Cycle, or dark reaction – the H+ from the split water and CO2 form 3 carbon sugars which in turn can form glucose, starch or cellulose
• Respiration and photosynthesis are continuous and opposite processes
• Equations


  • Respiration: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP
  • Photosynthesis: 6CO2 +6 H2O + light energy → C6H12O6 + 6O2
• Cell Cycle


  Includes interphase and mitosis
• Mitosis


  1. Reproduction of Body cell (skin, hair, bone, etc.)

  2. 4 phases: Prophase, Metaphase, Anaphase and Telophase, followed by Cytokinesis

  3. Two identical daughter cells are produced

  4. The chromosome number stays the same
• Diploid


  2n = 46 chromosomes
• Haploid


  n = 23 chromosomes
• Meiosis


  1. Reproduction of gametes (sex cells)

  2. Each cell goes through 2 cell divisions producing 4 HAPLOID gametes

  3. Allows variety
• Prokaryotes such as bacteria divide by the process of binary fission. These simple cells have no nucleus to surround the DNA. The cells produced are identical.
• Dominant genes


  Represented with a capital letter
• Recessive genes


  Represented with a lower case letter, often hidden by a dominant gene
• Genotype


  The gene make-up
• Phenotype


  The PHYSICAL expression of the genes
• Homozygous


  Gene pair has 2 like genes for a trait
• Heterozygous


  Gene pair has 2 different genes