1. Organic Compounds
Always contain carbon and hydrogen & generally Oxygen
Usually long chain of Carbon atoms linked by covalent bonds
The carbon atoms typically form additional bonds with Hydrogen or Oxygen.
Make up 40% of body mass.
4 Main Classes: Carbohydrates, Lipids, Proteins, and Nucleic Acids.
Known as macromolecules or Polymer;
Lipid is not a polymer.

2. Functional groups of Organic Compounds
Carboxyl Group –COOH : Acts as an acid, releasing H bonds to become R…--COO - Examples are Fatty acids and Amino Acids
Amino Group –NH2 Can accept or release H bonds depending on the pH. An example is Amino acid
Hydroxyl Group –OH Strong base dissociate to release hydroxide ions ( OH-) Examples Carbohydrates, amino acids, and fatty acids.
Phosphate Group –PO-34 Links other molecules to form larger structures. Stores energy in high NRG bonds. Example: phospholipids, nucleic acids.

3. Carbohydrates
Sugars and Starches that make up roughly half of U.S. diet.
Important for energy sources that are catabolized rather than stored.
3 sizes of carbohydrate molecules
monosaccharides
disaccharides
polysaccharides
Diverse group of substances formed from C, H, and O
ratio of one carbon atom for each water molecule (carbohydrates means “watered carbon”)
Main function is source of energy for ATP formation
Forms only 1 % of total body weight
glycogen is storage form of glucose in liver and muscle tissue
sugar is also the building blocks of DNA & RNA (deoxyribose & ribose sugars)

4. Monosaccharides Called simple sugars Contain 3 to 7 carbon atoms
We can absorb only 3 simple sugars without further digestion in our small intestine
glucose found in syrup or honey (metabolic fuel)
fructose found in fruits
galactose found in dairy products

5. Disaccharides
Formed by combining 2 monosaccharides by dehydration synthesis (releases a water molecule)
sucrose (table sugar)= glucose + fructose
Maltose = glucose + glucose
Lactose = glucose + galactose
All carbs except monosaccharides need to be broken down by hydrolysis before they can provide useful energy.
Sugars can be stored as fat for energy.

6. Polysaccharides: Complex Carbohydrates
Contain 10 or 100’s of monosaccharides joined by dehydration synthesis.
STARCH: The storage form of glucose in plants. High concentrations of glucose in plant or animal cells is TOXIC. Surplus stores of glucose is converted to starch for safety.
Glycogen is the storage form of glucose in animals. Glycogen is stored in the liver (hepatocytes) and in muscle cells. If serum glucose levels fall, glycogen is converted into glucose
Cellulose: can only digest small amounts via bacterial action. Cellulose is called dietary fiber. Water soluble found in fruits veggies. Insoluble fiber is in nuts and grains.

7. Carbohydrates Polysaccharides or polymers of simple sugars
Starch-Plants; Glycogen-Animals

8. Lipids or fats Formed from C, H and O includes Fats, oils, waxes,
18-25% of body weight
Hydrophobic
insoluble in polar solvents like water
Can combines with proteins for transport in blood (lipoproteins LDL’s, HDL’s )
They form the essential structural component of all cells
5 Classes: Fatty acids, eicosanoids, glycerides, steroids, phospholipids.

9. Triglycerides
Neutral fats composed of a single glycerol molecule and 3 fatty acid molecules
three-carbon glycerol molecule is the backbone
Very concentrated form of energy
9 calories/gram compared to 4 for proteins & carbohydrates
our bodies store triglycerides in fat cells if we eat extra food. Major source of stored energy in the body.
Fatty Acids help make up Triglycerides in 2 forms. SATURATED & UNSATURATED.

10. Triglycerides 3 fatty acids & one glycerol molecule
Fatty acids attached by dehydration systhesis

11. Triglycerides continued
Saturated fatty acids are found in animal products and are solid at room temperature and linked to cardiovascular disease.
Unsaturated Fatty Acids are liquids at room temperature and found in plants.
Margarine is made of corn oil a polyunsaturated fatty acid. Corn oil is hydrogenated by bubbling hydrogen gas through it. Hydrogenating polyunsaturated fats produces trans fats which are harmful to the body.

12. Oils & Waxes
Oils are very similar to polyunsaturated fatty acids. Oils are lipids that are liquids at room temperature. Oils we produce act as natural sun block, barrier to bacteria and lubricant for skin.
Waxes- Are lipids that are solid at room temperature. Produced to protect dust particles form entering the external canal.

13. Phospholipids
Consists of a lipid molecule joined to a phosphate containing organic group.
They act as the structural component of the cell
They have a phosphate group ( hydrophilic end )
They have a lipid ( Fatty Acids tails) ( hydrophobic end)
Composition of phospholipid molecule
a polar head
a phosphate group (PO4-3) & glycerol molecule
can form hydrogen bonds with water
2 non-polar fatty acid tails
interact only with lipids
Composition of cell membrane
double layer of phospholipids
Participates in transport of lipids in plasma

14. Phospholipids Composition of phospholipid molecule a polar head
a phosphate group (PO4-3) & glycerol molecule
can form hydrogen bonds with water
2 nonpolar fatty acid tails
interact only with lipids
Composition of cell membrane
double layer of phospholipids
Participates in transport of lipids in plasma

15. Chemical Nature of Phospholipids
head
tails

16. Four Ring Structure of Steroids

17. Steroids and Eicosanoids
Cholesterol- structural basis of all body steroids. We ingest it form eggs, milk, cheese, and our liver makes 80% of what we need.
Bile salts-these breakdown products of cholesterol are released by the liver into the digestive tract, where they aid in fat digestion and absorption.
Vitamin D- A fat soluble vitamin produced in the skin on exposure to UV radiation. Needed for bone growth and calcium absorption, and immune function.
Sex hormones- Estrogen and progesterone(female) and Testosterone(male). Needed for normal sexual function
Adrenocorticol hormones- Cortisol and Aldosterone
Eicosanoids: Lipid type derived from a fatty acid called arachidonic acid (e.g. Prostaglandins)

18. Proteins The most abundant organic component of the body.
Functions consist of:
Support- Structural proteins: framework of the body providing strength. Collagen, keratin, elastin
Movement- Contractile proteins needed for muscle contraction. Actin any Myosin.
Transport proteins- Hemoglobin transports oxygen in blood. Lipoproteins transport lipids and cholesterol.
Buffering- Assist in pH changes. Albumin acts as acid and base to prevent wide swing in Ph.
Catalysis- ENZYMES accelerate chemical reactions in cells.
Regulation of metabolism- growth hormone, insulin.
Defense- Tough waterproof proteins of the skin, hair, nails protect the body from hazards. Proteins called antibodies are components of the immune system, helps protect us from foreign matter.
Special clotting proteins restrict bleeding after an injury to the cardiovascular system.

19. Proteins 12-20% of body weight
Contain carbon, hydrogen, oxygen, and nitrogen
Constructed from combinations of 20 amino acids.
dipeptides formed from when 2 amino acids joined by a covalent bond called a peptide bond
polypeptides chains formed from 10 to 2000 amino acids.
Levels of structural organization
primary, secondary, tertiary, and Quaternary
shape of the protein influences its ability to form bonds

20. Amino Acid Structure Central carbon atom Amino group (NH2)
Carboxyl group (COOH)
Side chains (R groups) vary between amino acids

21. Peptide bonds

22. Structure of Proteins
Primary – sequence of amino acids
Secondary- folding of amino acids in beta sheets or alpha helices held in place by hydrogen bonds (interaction between side chain molecules)
Tertiary – overall 3D shape of polypeptide
Quaternary – interaction between subunits

23. 3 dimensional structure of proteins

24. Enzymes are Protein* Catalysts
Catalysts are not used up in the reaction
Each enzyme performs a specific reaction.
Enzymes end in “ase” (ex: catalase)
* All the enzymes are NOT proteins.

25. Enzymes Reduce Activation Energy

26. How do enzymes work?
Reactants (Substrate) bind to enzyme’s active site
“Induced Fit” Hypothesis

27. Factors that affect enzyme activity
Substrate concentration
Enzyme concentration
Temperature
pH of the reaction

28. Nucleic Acids - DNA & RNA
Huge molecules containing C, H, O, N and phosphorus
Each gene of our genetic material is a piece of DNA that controls the synthesis of a specific protein
A molecule of DNA is a chain of nucleotides
Nucleotide = i)nitrogenous base (A-G-T-C) + ii)pentose sugar + iii) phosphate group
This is DNA- Double Helix
Main function is storage & transfer of information essential for synthesis of proteins.

29. Nucleic Acids
Nucleic acids are macromolecules assembled from repeating monomers called nucleotides
DNA (deoxyribonucleic acid) stores hereditary information responsible for inherited traits in all eukaryotes and prokaryotes and in a large group of viruses
RNA (ribonucleic acid) is the hereditary molecule of another large group of viruses; three major types of RNA are involved in protein synthesis
pyrimidines
Nitrogenous bases with one carbon-nitrogen ring
Uracil (U), thymine (T), and cytosine (C)
purines
Nitrogenous bases with two carbon–nitrogen rings
Adenine (A) and guanine (G)

30. Nucleic Acids

31. A. DNA
B. RNA
Bases
Bases
Phosphate groups
Phosphodiester bond

32. DNA Base Pairs
The two nucleotide chains of a DNA double helix are held together by hydrogen bonds between the base pairs
A base pair consists of one purine and one pyrimidine
Adenine pairs only with thymine (A–T), forming two stabilizing hydrogen bonds
Guanine pairs only with cytosine (G–C), forming three hydrogen bonds

33. RNA Molecules
RNA molecules exist mainly as single polynucleotide chains (single-stranded) – however, RNA molecules can fold back on themselves to form double-helical regions
RNA contains ‘ribose’ not ‘deoxyribose’
In RNA, the uracil (U) base takes the place of thymine (T), forming A–U base pairs
Types of RNA within the cell, each with a specific function.
messenger RNA
ribosomal RNA
transfer RNA

34. Adenosine Triphosphate (ATP) High energy compound
ATP is needed for: muscle contraction, transport of substances across cell membranes, movement of structures within cells and movement of organelles
Consists of 3 phosphate groups attached to adenine & 5-carbon sugar (ribose)
Hydrolysis of ATP (removal of terminal phosphate group by enzyme -- ATPase)
releases energy
leaves ADP (adenosine
diphosphate)
Synthesis of ATP:
enzyme ATP synthase
catalyzes the addition of
the terminal phosphate
group to ADP