Cell Biology Unit Two

Covalent Bonds Bonds formed by the sharing of electrons between atoms

aaaaaaaaaaaaa - a covalently bonded, polar molecule Molecules are said to be polar if they have slight opposite charges on either end

The slight attraction between the negative end of one molecule and the positive end of another results in a… aaaaaaaaaaaaaaaaa

aaaaa - polarity leads to adhesion and cohesion - adhesion and cohesion cohesion lead to capillary action and surface tension - high specific heat leads to temperature stability - high heat of vaporization leads to evaporative cooling

aaaaa - This characteristic means water has a high degree of solvency and chemical reactivity - spheres of hydration form electrostatic interactions, keeping ions from interacting with each other

The Importance of Macromolecules

Definitions Dehydration synthesis – the assembling of organic molecules by extracting water Hydrolysis – the breaking up of organic molecules using water Self assembly – having the capability to form complicated from information inherent to the polymer

The Metabolism of Macromolecules

The four types of organic compounds Carbohydrates Lipids Proteins Nucleic acids

The general formula is CH2O The monomers are monosaccharides Functions: Provide energy Structural uses Examples: Plants - starch, cellulose, Animals - glycogen, chitin

Two functional groups – COOH- (carboxyl) and NH2- (amine) The monomers are amino acids Functions: Provide energy Structural uses Regulation Protection

Examples: Collagen Hormones Enzymes Antibodies

The monomers are nucleotides Functions: Heredity Protein synthesis aaaaaaaaaaa Nitrogen base Pentose sugar Phosphate group

Examples: DNA RNA Single stranded with three forms – tRNA, rRNA, and mRNA Double stranded, double helix molecule

Functional group – COOH- (carboxyl) The monomers are fatty acids and alcohols Functions: Storage energy Structural uses Regulation Protection

Examples: Fats (triglycerides) Phospholipids Steroids Waxes

The two types of fatty acids Saturated Unsaturated

Adenosine triphosphate The fuel of living cells

Nicotinamide adenine dinucleotide (NAD + ) Small molecules that act as electron carriers

Nine Protein Types

Hydrophobic Amino Acids

Hydrophilic Amino Acids

Protein Organization

Protein Organization

Protein Organization Covalent bonds Hydrogen bonds Ionic bonds

Protein Organization van der Waals interaction Hydrophobic interactions

Protein Organization Secondary Structure Tertiary Structure

Protein Organization Quaternary Structure

Enzymes PPPProteins that function as biological catalysts by lowering the energy of activation and speeding up chemical processes EEEEnzymes are substrate specific, much like a lock and key EEEEnzymes catalyze reactions without being changed

Enzymes HHHHow they work!

Enzymes HHHHow they work!

Enzymes HHHHow they work!

Cofactors inorganic metal ions Ca2+, Mg2+, Cu2+ and others change the shape of the enzyme Coenzymes organic molecules derived from vitamins NAD+ and FAD+ and others carry H+ and small molecules

Enzymes Allosteric site

pH effects on enzymes Temperature effects on enzymes

Regulation of activity Concentration of enzymes Concentration of substrates Concentration of cofactors Enzymes Concentration of coenzymes Various types of inhibition

Enzymes Allosteric inhibition

Enzymes Competitive inhibition

Enzymes Noncompetitive inhibition

Enzymes Feedback (end product) inhibition

Nucleic Acids

Nucleic Acids

Nucleic Acids

Nucleic Acids

Nucleic Acids

Nucleic Acids

Carbohydrates Pentose sugar Hexose sugar

Carbohydrate s Disaccharides

Carbohydrate s Polysaccharides

Lipids Lipid Classes

Lipids Phosphatidic Acid

Lipids Steroid Examples