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BiochemistryBio I HonorsRupp

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WaterTwo hydrogens and

one oxygen bonded covalently

Electrons are not shared equally—oxygen is very electronegative

The uneven charge is known as polarity◦ Oxygen is negative◦ Hydrogens are

positive

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PolarityThe uneven

charge of water is what makes it good at dissolving other substances◦ Sugars◦ Proteins◦ Ionic compounds

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Water’s Physical PropertiesHigh surface

tensionHigh specific heatCohesion

◦ Attractive force between particles that are the same

Adhesion◦ Attractive force

between unlike particles

CapillarityUniversal solventNeutral pHHydrogen

bonding

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Water’s Physical Properties

Surface tension Cohesion

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Water’s Physical Properties

Adhesion Hydrogen bonds

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Carbon CompoundsCarbon has four outer electronsCarbon can form how many bonds?Types of bonds

◦Single◦Double◦Triple

Structures◦Straight chains◦Branched◦Rings

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Carbon Structure

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Carbon Structure

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Functional GroupsGroup Name Group Structure

Alcohol -OH

Aldehyde -CHO

Ketone -CO

Carboxylic acid -COOH

Amine -NH2

Phosphate -PO4

Sulfhydryl -SH

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PolymersMacromolecules or polymers are built

from single units called monomersDehydration synthesis or condensation

reaction joins two monomers◦Water is lost◦Building

Hydrolysis reactions break apart polymers into monomers◦Water is added◦Breaking

Energy used for both processes—ATP

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Dehydration Synthesis vs. Hydrolysis

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CarbohydratesComposed of

carbon, hydrogen, and oxygen

Sugars ◦ Monosaccharides◦ Disaccharides◦ Polysaccharides

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MonosaccharidesBasic formula is

C6H12O6Triose—3

carbonsPentose—5

carbonsHexose—6

carbons

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DisaccharidesBasic formula is

C12H22O11Two monosaccharides

have been linked and a water lost

The bond holding the sugars together is a glycosidic bond

Isomers—same chemical formula with different structures

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Polysaccharides

Storage Structural

StarchSimplest starch is

amylose, which is found in plants

Amylopectin is more complex with more branches

Glycogen is a highly branched animal starch

Cellulose and chitinCellulose is the most

abundant organic compound on Earth

Chitin is found in shells of crustaceans and insects

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Proteins Made of carbon,

hydrogen, and nitrogen

Monomers are amino acids linked through dehydration synthesis

Essential amino acids—need to be consumed because your body cannot make them

Lysine and tryptophan are two amino acids

Poorly represented in vegetarian diets

Lysine is found in chicken, turkey, potatoes, cheese, soy, eggs, milk, fish, and beef

Tryptophan is found in almonds, cabbage, kidney beans, lima beans, oats, pistachios, poppy seeds, spinach, and wheat

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Proteins con’t. Peptide bond is

the bond between amino acids

Many amino acids means many peptide bonds, hence proteins are referred to as polypeptides

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Proteins con’t.What are proteins good for?

◦Structural support◦Storage of food sources◦Transport proteins◦Hormones◦Antibodies◦Enzymes

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Proteins con’t.Different protein

shapes◦ Globular◦ Fibrous◦ Membranous

Enzymes◦ Special proteins

that speed up reactions; biological catalysts

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LipidsFatty acid chains

—referred to as acids because of the carboxylic acid functional group

Two subgroups◦ Saturated◦ Unsaturated

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Lipids con’t.

Saturated Unsaturated

Solid at room temperature

Found mostly in animals

No double bonds between carbons

Liquid at room temperature

Found mostly in plants

Double bonds between carbons

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Lipids con’t.Trans fatty acids

—also known as partially hydrogenated fats (check food labels)◦ Not good for you◦ Manufactured to

have more taste than unsaturated fatty acids

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Omega 3 Fatty Acids—Good LipidsHelp in cell

membrane formation—keeps them flexible

Deficiencies linked to:◦ Decreased mental

ability◦ Poor vision◦ Increased blood clots◦ Diminished immune

function◦ High blood pressure◦ Learning disorders◦ Growth retardation

Found in:◦ Walnuts◦ Pumpkin seeds◦ Brazil nuts◦ Avocados◦ Spinach◦ Collard greens◦ Salmon◦ Mackerel◦ Albacore tuna

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Omega 6 Fatty Acids—Good Lipids Help improve:

◦ Diabetic neuropathy

◦ Rheumatoid arthritis

◦ PMS◦ Skin disorders

such as psoriasis and eczema

Found in:◦ Grapeseed oil◦ Pumpkin seeds◦ Pinenuts◦ Pistachios◦ Raw sunflower

seeds◦ Olives◦ Chicken

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PhospholipidsVery similar to

fatty acids except there is a phosphate group attached

Polar phosphate group and non-polar fatty acids

Found in cell membranes

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WaxesA type of

structural lipidHighly waterproof

◦ Found on plant leaves to prevent water loss

◦ Also found on animals as a protective layer against microorganisms, Ex., earwax

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Nucleic AcidsDNA—deoxyribonucleic acid

◦ “deoxy” implies a certain sugar typeRNA—ribonucleic acid

◦ “ribo” implies a certain sugar typeBoth are composed of thousands of

monomers called nucleotidesThree parts to each

◦ Phosphate◦ Sugar◦ Nitrogenous base

Monomers are connected by phosphodiester bonds

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Nucleic Acids con’t.

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Nucleic Acids con’t.