Functional Groups A group of atoms within a molecule that interacts in predictable ways with other molecules. Examples? Hydroxyl groups are hydrophilic

H

Monomers – small molecular units Polymers – long chain of many monomers put together.

Building Polymers Dehydration reaction – removes water. Each time a monomer is added to a chain, a water molecule is released.

Breaking Polymers Hydrolysis reaction: water is used (added) to break down the polymer. Polymers need to be broken down to make monomers available to your cells.

Carbohydrates An organic compound made up of sugar molecules. Sugars –1 C: 2 H: 1 O –Main fuel supply for cells

Monosaccharides Simple sugars Contain just one sugar unit Examples: Glucose, fructose, galactose

Disaccharides Two monosaccharide put together Example: sucrose

Polysaccharides Many monosaccharides linked together Examples: –Starch - found in plant cells, made up of glucose monomers.

Polysacchardies (con’t) –Glycogen Found in animals cells Glucose monomers linked together Highly branched

LIPIDS Hydrophobic compounds Example: Our cells!, Fats, Steroids

FATS A 3-carbon backbone (glycerol) attached to 3 fatty acids.

Saturated Fat –Fatty acid chains contain the maximum number of hydrogen bound to them –Solid at room temp. Unsaturated Fat –Have double bonds between Carbon atoms

Steroids Lipid molecule in which the carbon skeleton forms four fused rings. Uses: –Chemical signals in body Cholesterol is a type of steroid

Proteins

Functions Include: Make up hair & muscles Defend our bodies from harmful microorganisms Convey messages between cells Control chemical reactions in cells

Structure Polymers made up of monomers (amino acids) 20 different amino acids

Amino Acids C N H H C O OH H SIDE GROUP Carboxyl Group Amino Group **COVALENT BONDS**

Building a Protein C N H H C O OH H SIDE GROUP C N H H C O OH H SIDE GROUP WATER Amino Acids are linked into a chain called a polypeptide Each link is created by a dehydration reaction. What two groups come together for this to happen?

Protein Variety Different proteins are made by arranging different amino acids in different orders

Protein Shape Amino acid sequence is important in determining protein shape. –Example: Some side groups bind with each other to help fold the polypeptide.

Denaturation The loss of the normal shape of a protein –Causes: unfavorable temperature change, pH change Denaturation results in a lack of ability to work properly

ENZYMES Type of protein that serve as a catalyst.Type of protein that serve as a catalyst. – Catalyst: Compounds that speed up chemical reactions. – Catalysts work by lowering the activation energy of a reaction.

Activation energy is the minimum amount of energy needed to trigger a chemical reaction.

Enzyme Function Enzymes are specific: the shape of each enzyme fits only certain reactants (substrate). –Substrate: specific reactants acted upon by an enzyme. Substrates fit into a region of an enzyme called the active site.

Once the Enzyme Binds the Substrate The active site changes shape, which allows it to catalyze the reaction. The tighter grip may also bend the substrate making the bonds weaker and easier to break.