Subatomic Particles

nucleus - protons(positive charge), neutrons (no charge)

electrons - negetively charged particles that orbit the nucleus (1837 electrons = the mass of one proton)

scale of an atom

Atomic Number/Mass Number

Isotope-Explanation of Isotopes (advanced)

Electron Shells-Electron Shell Tutorial (advanced)

Element- a substance made of only one kind of atom

Four elements make up approximately 96% of you and all living things
What elements are you formed of?
  • Oxygen 65%
  • Carbon 18.5%
  • Hydrogen 9.5%
  • Nitrogen 3.2%
  • Calcium (1.5%)
  • Phosphorus (1.0%)
  • Potassium (0.35%)
  • Sulfur (0.25%)
  • Sodium (0.15%)
  • Magnesium (0.05%)
  • Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)
  • Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts)
Elements in the Human Body

Compound - two or more elements in exact proportion

Compounds are held together by the energy of chemical bonds
compounds have properties that are different from the elements that make them up

Types of Compounds (advanced)
Molecular Compound-formed from covalant bonds covalent bonds are formed when valance(outer shell) electrons are shared between two or more atoms) co=share / valance=outer shell electrons
Ionic Compound- formed when ions of opposite charges attach to one another to form an electrically neutral compound

Build a Molecule Simulation

Water- essential compound for living organisms
  • A molecule of water has one oxygen atom bonded to two hydrogen atoms.
  • The unequal shearing of electrons causes the oxygen side of water to have a negative charge and the hydrogen sides of the molecuel to have positive charges. This results in water forming hydrogen bonds.

Water Unique Characteristics Summary

  • polar with positive and negative side that causes hydrogen bonding -->leads to cohesion
  • unique properties that assist with life

1. high specific heat - water does not change temp easily making it an insulator

2. solvent-- breaks down other polar substances allows them to be transported throughout the body

3. ice floats- keeps supply of liquid water available on earth

4. capillary action -- helps move water through xylem cells in plants


notes from text

  • Nucleic Acids
    1. macromolecules formed from chains of nucleotides
    2. function: provides genetic information (genetic blueprint)
    3. examples: DNA and RNA
    4. DNA makes RNA
    5. RNA makes Protein

  • Proteins
    1. Constructed from long chains of amino acids
    2. RNA contains instructions for making protein
    3. Examples from text: Amalyse (digestion) and Keratin (structure and support)
    4. Examples of function from text(necessary for all cellular activities)
      • digestion
      • structural support
      • transport
      • communication

  • Lipids
    1. large molecules that do not dissolve in water (non-polar)
    2. form protective barriers
    3. Examples from text: cholestertol, phospholipids, vitamin A
    4. Examples of functions from text
      • make up cell membranes
      • store energy
      • communication

  • Carbohydrates
    1. One sugar molecule, two sugar molecules or a long chain of sugar molecule( ratio= one hydrogen: 2 carbon: 1 oxygen)(example glucose C6H12O6 )
    2. Function
      • store energy
      • structural support
      • communication
    3. Examples
      • sugars (release energy quickly)
        • Fruit
      • Starches
        1. Bread
        2. Pasta
      • Cellulose (plant-structural support)