Anatomy Chapter 2

• Anything that has mass and volume.
• 1) Solid 
• 2) Liquid
• 3) Gas

Elements are basic unit of unique substances 

Elements always have the same number of protons. (also atomic numer)

Organized on the periodic table with each element on the periodic table assigned an atomic symbol

Most common biological elements (96%): carbon, hydrogen, Oxygen, and nitrogen (CHON) Required by life

Trace emements: Zinc Copper, etc. Required by life

• Atoms are the basic unit of life
• Protons- Positively charged 
• Determines type of element if is (Atomic Numer)

• Neutron- No Charge
• inside the atom's nucleus 
• The number differs in isotopes 
• Radioisotopes give off radiation 
• Radioisotopes are used for PET scans , bone scans, thyroid monitoring and cancer treatments 

• Electrons- are negatively charged 
• Speedily flies around atom's nucleus in a cloud called and Orbital
• Electrons are responisble for bonding (holding more than one atom together)

• Atoms can be bound together 
•   1) Molecules: When 2 or more atoms are bound together 
• Atoms bond to fill their shells 

 2) Proper way to write bonding reaction: A + b --> C ( A and B are reactants and C is the product molecule; Chemical eqautions are balanced  

• electron shells- are areas around an atom's nucleus where electrons can be found 
•  1)First shell holds 2 electron 
•  2)Second/third shell holds 8

• bonding occurs between atoms that will fill-up the last (outermost) shell
•  1) Octet Rule: atoms with bond so that it has a valence shell
•   A) if less than 8 electrons in shell, can lose electrons so that lesser shell is full and now a valence shell 
•   B) if less than 8 electrons in shell, can share or gain electrons so that the current valence shell can be filled

goal of bonding is to fill the shells 

• Covalent bonds- Strongest bond.
•  A) electrons are shared and between atoms so that the valence shells are filled 
•  B) Can be single/double/thriple bonds (single/double bonds are common in biology) 

• Ionic Bonds- Second Strongest bond 
•  A)Electrons are lost and gained between atoms 
•  B)creates ion that are oppositely charged and attract to each other 
•  C) when in dry form it creates salt (not just table salt NaCl)
•  D) If you gain or loss an electron, you be come an ION

• Hydrogen bonds- Weakest bonds
•  A)Holds molecules close together 
•  B)responsible for surface tention and holding larger polar bonds together  

Inorganic chemicals- does not contain carbon (if you have carbon you are considered organic)

• Water
•  1) high heat capacity-takes a lot of energy to heat of  
•  2) is the solvent of life- you pour everything into it 
•     A)most reactions in the body happens in water (aqueous) solutions 
•          ii) water is the solvent
•          iii)chemical dissolved is the solution 

• Salt- an ionic bond and water soluble (mixes in water)
•  A)dissociate in ions in water 
•  B) in the body called electrolytes- salt inside your body 

• Acids and bases- 
• A) acids release H+ (protons) into a water solution

• B) bases (OH-)
•   1)binds to H+ and removes it from the solution

• C) pH-calculates acidity or basicityof solution
•        i) pH=7 is neutrul water ( life likes it here)
•        ii) pH <7 is acid, vinegar, and wine
•        iii) pH >7 is base, most soaps, ammonia (same as alkaline) 

Organic molecules (molecules that contains carbon) 

• A) 4 types of biochemical macromolecules 
•     i) carbohydrates (sugars/starches) 
•           1)human biology and carbohydrates
•                  a) Energy sources
•                        I)glucose is immidiate energy source
•                        II)glycogen is stored energy in liver and skeletal mucles
•                        III)Starch is energy stored by plants that we consume and use for energy 

•      ii) Lipids (diverse group of biochemical that includes fats, oils, wax, steroids)
•          1) all are non-polar molecules ( water replelling)
•          2)Triglycerides (neutral fats )
•                 a) fatty acids:long chains of non-polar hydrocarbons 
•                       i)saturated fatty acids:
•                              a) all single bonds
•                              b) solid at room temperature 
•                       ii) unsaturated fatty acids
•                               a)some double C= C bonds
•                               b) Liquid at room temperature
•                               c) Trans fats: unnaturally occurring unsaturated fats that are unhealthy
•                       iii) Phospholipids- outside of every cell
•                               a) chemical make up
•                               b)biological use- cell membrane 
•                      iv)steriods- cholesterol and hormones 

•     iii) Proteins- water soluble
•                a) chemical make-up
•                      i) momomers: Amino Acid
•                              a) 20 different types of amino acids
•                      ii) over all protein structure 
•                              a) Fiberous- strong, linear, stable, ie: collogen (long)
•                               b)Globular- (most common) rounded
•                                          i) water soluble
•                                          ii) mobile/flexble
•                                          iii) immune system
•                                          iv) Have Active Site
•                                          v) Unstable- teritiary structure often held together by many hydrogen bondsso broken by temperature and pH
•                 a) Enzymes- are proteins. Very important protein (names commonly ends in "ase"). Helps break down and build up, gets things rolling.
•                            i) Biological catalysts: speeds up reactions  
•                           ii) Makes specific reactuibs occur fast enough to help the body
•             a) other important proteins 
•                           i) antibodies- immune system recognition
•                           ii) signaling proteins- growth hormones, insulin
•                           iii)