chemistry of life part ii -chemical reactions -enzymes -water

Chemistry of LifePart II

-Chemical Reactions-Enzymes

-Water

Enzymes – catalysts or “biological wedges”Activation Energy – the necessary energy input to jumpstart a reaction

Energy of ReactionsEnergy-Absorbing Reaction Energy-Releasing Reaction

Products

Products

Activation energy

Activation energy

Reactants

Reactants

Endothermic Exothermic

Enzymes:-Regulate chemical pathways-Make materials that cells need-Release energy

Enzyme Video

• http://www.youtube.com/watch?v=CZD5xsOKres&feature=related

H20

Slight Negative Charge

Slight Positive Charge

Water’s Polarity

• 2 polar ends attract each other

• A weak bond between the H of one atom and the O of another in water (or any electroneg…)

• H20 can hydrogen bond with 4 other H20 molecules

hydrogen bonding-the attraction between water molecules

Properties of WaterUniversal Solvent-due to its polarity

-Salts, sugars, acids, bases-Hydrophobic vs hydrophilic

Cohesion Causes Surface Tension

Adhesion (Capillary Action)

http://discovermagazine.com/2003/mar/featscienceofhttp://www.sciencebuddies.org/science-fair-projects/project_ideas/PlantBio_p033.shtml

Dehydration synthesis- build up by removing water

Hydrolysis-break down by adding water

GOOD LUCK!!!