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Biochemistry Part 2. An acid is a substance that produces hydrogen ions (H+) when it is dissolved in water. A base is a substance that produces hydroxide ions (OH-) when it is dissolved in water.
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An acid is a substance that produces hydrogen ions (H+) when it is dissolved in water. A base is a substance that produces hydroxide ions (OH-) when it is dissolved in water. A pH scale ranks the substances according to the relative concentrations of their hydrogen ions. Substances with pH of less than 7 are considered acids, and higher than 7 are considered bases. When acids and bases mix, they undergo a neutralization reaction that results in the formation of salt and water Neutralization
Normal human blood pH is 7.35-7.45. • Alkalosis is when a person’s pH levels go up (high altitudes, anxious) • Acidosis is when the blood pH lowers to 7.1-7.3 and can cause fatigue. Above 7.8 and below 6.8 can be fatal • We need buffers that will maintain pH balance • A buffer system we have in our blood is the carbonic acid and hydrogen carbonate ion. • http://www.youtube.com/watch?v=l9dliAngF2k
Oxidation-Reduction Reactions • LEO says GER • Loss of elections: oxidation • Gain of elections: reduction • C6H12O6 + 6O2 -> 6CO2 + 6H2O Sugar is oxidized in a series of reactions to get energy.
Condensation Reactions • When you react two separate molecules to join and a water molecule is released. Also called a dehydration reaction.
Hydrolysis Reaction • When you breakdown macromolecules into its monomers using a water molecule.
Enzymes • A certain amount of energy is required to start any reaction. This is called the activation energy. • There are several ways to lower the activation energy or speed up a reaction: increase temperature (not recommended in living things) or use a catalyst. • A protein molecule can make biological catalysts called enzymes. • Every different reaction that occurs in our body has a certain enzyme that will facilitate the reaction.
Enzymes have specific 3D shapes with indentations on their surfaces called the active site where the substrate (reactants of the reaction) will bind. • When the substrate and enzyme are bound together, it is called the enzyme-substrate complex • The enzyme will then adjust its shape, allowing the reaction to happen easier
Some enzymes need the help of other organic molecules… called coenzymes • Some enzymes may need the presence of ions such as iron or zinc… called cofactors • Enzymes are classified based on the type of reaction they catalyze. For example, enzymes that catalyze hydrolysis reactions are called hydrolases. • Enzymes are specific • i.e. lactase
Enzyme activity can be affected by a change in condition that alters the enzyme’s shape (temperature and pH) • Inhibitors are molecules that interact with an enzyme and reduce the activity of the enzyme and its ability to bind with a substrate • Competitive inhibition: inhibitors that interact with the active site • Non-competitive inhibitors: bind to an allosteric site (not the active site, but changes the shape of the active site) • Activators: molecules that can also bind to an allosteric site, but change the shape of the active site to make it so the substrate CAN bind to the enzyme.