1. Biochemistry
The Chemistry of Life

2. Is chemistry really that important to learn about?
Of course it is!!!
Chemicals make up EVERYTHING in our bodies, as well as everything we eat!
Chemicals are EvERYwHErE!!!
4 important types of organic molecules are: Carbohydrates, Lipids, Proteins and Nucleic Acids

3. But first….a little review
Elements: simplest form of a substance - cannot be broken down any further without changing what it is
Atom: the actual basic unit - composed of protons, neutrons, and electrons

4. Atomic structure
Just like cells are the basic unit of life, the ATOM is the basic unit of matter.
They are very small. If placed side by side one million would stretch a distance of 1cm.
The atom is made up of 3 particles.
Particle
Charge
PROTON +
NEUTRON
NEUTRAL
ELECTRON -

5. Isotopes
atoms of the same element that HAVE A DIFFERENT NUMBER OF NEUTRONS
Some isotopes are radioactive. This means that their nuclei is unstable and will break down at a CONSTANT RATE over time.
There are several practical uses for radioactive isotopes:
CARBON DATING
TRACERS
KILL BACTERIA / CANCER CELLS

6. Ionic Bonds
Occur when 1 or more electrons are TRANSFERRED from one atom to another.
When an atom loses an electron it is a POSITIVE charge.
When an atom gains an electron it is a NEGATIVE charge
These newly charged atoms are now called IONS
Example: NaCl (SALT)

7. Covalent bonds Occur when electrons are SHARED by atoms.
These new structures that result from covalent bonds are called MOLECULES
** In general, the more chemical bonds a molecule has the more energy it contains

8. Water—The Mysterious Molecule
Because water (H20) is a polar molecule, it has many unique properties.
Slightly +Hydrogens are attracted to slightly –Oxygens
These attractions are called hydrogen bonds and are the reason water:
is the only substance that is less dense as a solid
Has a high specific heat/heat capacity
Is attracted to itself (cohesion) and other substances (adhesion)

9. pH scale In water, some H20 breaks apart into H+ and OH-
If the amount of each ion is equal, the solution has a pH of 7
The more H+, the more acidic the solution
0 – 6 acid
6-7 neutral
8-14 base

10. Carbon chemistry 4 valence electrons, Can form 4 bonds
Readily bonds with other carbons
Can form long carbon chains, or carbon rings
Can form single, double or even triple bonds

11. Molecules of Life Carbohydrates (CHO) Sugars and starches Lipids (CHO)
Polymer: Large molecule made up of repeating subunits
Monomer: smaller molecules that make up polymers
Carbohydrates (CHO)
Sugars and starches
Lipids (CHO)
Fats, oils, waxes and steroids
Proteins (CHONS)
Amino acids and enzymes
Nucleic Acids (CHONP)
DNA and RNA

12. Carbohydrates Monosaccharides (1C:2H:1O)
Glucose (made by plants during photosynthesis)
Fructose
Galactose

13. Carbohydrates, cont’ Disaccharides Polysaccharides Two monosaccharides
Sucrose (fructose + glucose)
Lactose (glucose + galactose)
Polysaccharides
3 or more monosaccharades
Starch (plant energy storage)
Glycogen (animal energy storage)
Cellulose (plant structure)

14. Lipids More C, less H and O Insoluble in water
Used for long term energy storage and insulation
Fatty Acids, Triglycerides, Waxes and Steroids

15. Lipids, cont’ Fatty Acids Make up most lipids
Long hydrocarbon chain with a carboxyl group (COOH) on one end
Carboxyl group is polar (hydrophilic)
Hydrocarbon chain is nonpolar (hydrophobic)
In a cell membrane, fatty acids are arranged in a double layer, with chains pointing towards eachother

16. Saturated fats vs Unsaturated fats
Hydrocarbon chain is ‘saturated’ with hydrogens (all single bonds)
Solid at room temperature
Usually animal based
                          
                                  

17. Unsaturated Fats Contain one or more double bonds
Liquid at room temperature
Usually plant based
                                       
                               

18. Proteins Contain H, O, C and Nitrogen
Main component of our body tissue
Made up of chains of amino acids
Amino acids = monomers
Polypeptide/protein = polymer

19. Proteins, cont’ Amino acids Monomers that form proteins
Basic structure: C with a carboxyl (COOH), amino (NH2), H and ‘R’ groups attached

20. Proteins, cont’ Enzymes
Specific proteins that speed up chemical reactions
Not affected by the reaction
“Induced fit” model (used to be called ‘lock and key’)

21. Nucleic Acids Complex polymers made of monomers called nucleotides
Store important information in the cell
Deoxyribonucleic acid (DNA)
Stores most of the information necessary for cell function
Ribonucleic acid (RNA)
Stores and transfers information for making proteins

22. Vocabulary check… Macromolecule Polymer Carbohydrate Lipid Protein
Amino acid
Nucleic acid
Nucleotide

23. FUNCTIONAL GROUPS
Functional groups are structural building blocks that determine the characteristics of a compound.
One functional group important to living things is the hydroxyl, represented by --OH.
(Table 3-1)
An alcohol is an organic compound with a Hydroxyl Group attached to one of its Carbon Atoms.
The hydroxyl group makes alcohol a polar molecule, which means it is soluble in water
Other functional groups important to living things are shown in Table 3-1.

24. A little more about enzymes…
Most of the reactions that take place in our body require enzymes.

25. OUCH!!!!!!!

26. **EXTRA CREDIT OPPORTUNITY**
Speaking of fatty acids…
Find out:
What trans-fatty acids are (trans fats)
How they are formed
Why they are not good for us
What kind of foods have them
Turn in by Friday for 5 EC points

27. How are they formed? Dehydration Synthesis
Sometimes called a condensation reaction
2 monomers + energy + enzymes 
polymer + H2O

28. How are they broken down?
Hydrolysis reaction
Reverse of a dehydration synthesis reaction
Hydro = water
Lysis = breaking apart
Requires enzymes
Releases energy (heat)

29. Lipids, cont’ Triglycerides
Three fatty acid chains joined to one molecule of glycerol
Either oil or fat depending on state at room temperature

30. Lipids, Cont’
Waxes
Long fatty acid chain joined to a long alcohol chain
Highly waterproof
Protective barrier in plants and animals (earwax)

31. Lipids, cont’ Steroids Unlike other lipids, composed of 4 carbon rings
Considered lipids because they are insoluble in water
Ex. Hormones, nerve tissues, venoms, plant poisons