Carbon, Macromolecules and Metabolism

I. Carbohydrates – Sugars, Starch, & Chitin

Monosaccharides-glucose, maltose, sucrose, fructose and galactose
Disaccharides – a covalent bond formed between two monosaccharides joined by a glycosidic linkage in a dehydration reaction.

Polysaccharides – have a few hundred to a few thousand monosaccharides.
1. Starch: storage polysaccharide for plants
2. Glycogen: storage polysaccharide for animals
3. cellulose: defensive polysaccharide for plants-the most abundant organic compound on Earth (100billion tons annually) few organisms possess enzymes that can digest cellulose.
4. Chitin – exoskeletons hardens with carbonate.

II. Lipids, Hydrophobic Molecules
The fats Glycerol with three fatty acids hanging off of it.
1. Saturated fats, nothing but single bonds on the carbons
2. Unsaturated fats, have double or triple bonds along the fatty acids.

Hydrogenated vegetable oils mean that unsaturated fats have been synthetically converted to saturated fats by adding hydrogen. (Canada-Oreo Cookie Hydrogenation Plant with Lard!)
Phospholipids – cell membranes & micelle
Steroids – ringed structures

III. Proteins, the workhorses of cells
Polypeptides – polymers of amino acids that make up proteins.

Four levels of Protein Structure
1. Primary Structure – the sequence of amino acids
2. Secondary Structure – coiled or folded pattern
3. Tertiary Structure – hydrophobic interactions, disulfide bridges p.77
4. Quaternary Structure – aggregation of multiple polypeptide subunits.

Protein Structure can be disrupted by:
1. pH, salt concentration, temperature this unraveling of the protein is called denaturation.
2. chaperonins – protein molecules that assist the proper folding of other proteins.

IV. Nucleic Acids – Informational Polymers
DNA – deoxyribonucleic acid
RNA –ribonucleic acid
DNA provides directions for its own replication and directs synthesis for RNA. Through RNA controls the protein synthesis.
Pyrimidines (Only Thymine is in DNA and only Uracil is in RNA) & Purines

Only 5 nucleic acids
C - Cytosine
T – Thymine (DNA)
U – Uracil (RNA)
A - Adenine
G – Guanine

Metabolism, Energy & Life
Metabolism – totality of an organism’s chemical reactions.
Catabolic pathways – release energy for use of the organism/cell
Anabolic pathways – consume energy to build complicated molecules.
Bioenergetics – the study of how organisms manage their energy resources.
Thermodynamics – the study of energy transformations that occur in a collection of matter.
The first law of thermodynamics: Energy can be transferred and transformed, but it cannot be created or destroyed. Principle of conservation of energy.
The second law of thermodynamics: Every energy transfer is increasing the entropy of a closed system.
Conversion to heat is the fate of all the chemical energy…
The Quantity of the energy in the universe is constant, but its quality is not.

Gibbs Free Energy:
Metabolic Disequilibrium is required for life. If a cell ever reached a ΔG=0, it would be dead!!!
Energy Coupling - the use of a exergonic process to drive an endergonic one. ATP can mediate this for cells.

Enzymes:
Catalyst – a chemical agent that changes the rate of a reaction without itself being consumed. An enzyme is nothing more than a catalytic protein.


AS405 –Day 2 Homework Name: ____________________


1. What are the four forces in our Universe and their effect?




2. What are the four major polymers and their respective monomer subunits called?






3. List the four major chemical bonds and give examples of each.






4. List the six major functional groups and give their structures.





5. List the five nucleic acids and give their structure.