BIOM 250 1st Edition Lecture 3Outline of Last Lecture I. Types of MicroorganismsII. MicrobesIII. Compound Light MicroscopyIV. StainingOutline of Current Lecture I. AtomsII. Chemical BondsIII. Chemical ReactionsIV. Inorganic CompoundsV. Organic CompoundsCurrent LectureI. Atomsa. Consist of protons, neutrons, and electronsb. Protons give weightc. Electrons (in outer shells) give reactivityd. Atomic number- based on the number of protons in an atome. Atomic weight- based on all components (mass)II. Chemical Bondsa. Ionic bond-loss of an electron by one element, and the gaining of an electron by anotheri. Occurs when opposite charges attractb. Covalent bonds- electrons shared; makes strong bondsc. Hydrogen bonds- occurs when a hydrogen atom (positively charged) in a covalentbond is attracted to another atom (negatively charged); weak bondThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.III. Chemical reactions- the making or breaking of bonds between atomsa. Endergonic reaction- absorbs more energy than is releasedi. Occurs when atoms, ions, or molecules, combine to form new, larger moleculesii. Also called anabolic or synthesis reactionb. Exergonic reaction- releases more energy than is absorbedi. Occurs when a molecule is splitii. Also called a catabolic or decomposition reactionc. Exchange reaction- part synthesis and part decomposition reactioni. Example: NaOH+ HClNaCl + H20ii. Notice how the elements switch around in the above exampleIV. Inorganics in Biologya. Water- characterized by its polarityi. Forms hydrogen bonds with other water moleculesii. Dissociates other polar substancesiii. Key reactant in many biological reactionsiv. Temperature bufferb. Acid/Base Reactionsi. Acids dissociate—release H+ ionsii. Bases dissociate—release OH- ionsiii. Measured by pH, which is based on a logarithmic scaleiv. View a pH scale to aid in your understandingV. Organic Compoundsa. Definition-i. Always contain carbon and hydrogenii. Are usually structurally complexb. Functional Groups- molecular side groups that take part in chemical reactionsi. Determine chemical and physical properties of organic compoundsc. Carbohydrates- molecules made from carbon, hydrogen, and oxygen; polari. Monosaccharides1. Simple sugarsii. Disaccharides- formed by dehydration synthesis between two monosaccharides iii. Polysaccharides-many monosaccharides joined together by dehydration synthesisd. Lipids-molecules made from carbon, hydrogen, and oxygeni. Non polar, which makes them insoluble in waterii. Simple Lipids- fats or triglycerides1. Formed from glycerol + fatty acid(s)2. Fatty acid- long chain of hydrocarbons with a carboxyl group end3. Can be saturated (no double-bond in carbon chain) or unsaturated(one or more double bonds)iii. Complex lipids- Contains elements such as phosphorous, nitrogen or sulfur1. Form an amphipathic molecule2. Basic component of the plasma membrane3. Example- phospholipids which have a hydrophilic end and a hydrophobic endiv. Steroids- contain four carbon rings with an –OH attached to one ring1. Important component of animal plasma membranese. Proteins-nitrogenous organic molecules, many different types in each celli. Amino acids- building blocks of proteins1. Contain at least one carboxyl group and one amino group attached to an alpha-carbon2. Side group, or R group, is also attached to the alpha-carbon3. R group determines the properties of the amino acidii. Stereoisomers- mirror images of a molecule1. Configured as D or L-isomers2. Animal proteins made from L isomer3. Some microbial proteins contain D- isomers iii. Peptide bonds- bonds that form between the carbon of a carboxyl group and nitrogen of an amino group by a dehydration synthesis1. Form peptides (2-9 amino acids) or polypeptides (10-2000) amino