BACE Practical Review (2023/2024) Graded A

BACE Practical Review (2023/2024) Graded A Restriction Enzyme (Restriction Endonuclease) An enzyme produced chiefly by certain bacteria, having the property of cleaving/cutting/digesting DNA molecules at or near a specific sequence of bases. Spectrophotometer Used to measure protein or DNA concentration; an apparatus for measuring the intensity of light in a part of the spectrum, especially as transmitted or emitted by particular substances. Horizontal Gel Electrophoresis Box Used to run DNA agarose gels. Vertical Gel Electrophoresis Box Used to run protein gels (PAGE or polyacrylamide gel electrophoresis). Buffer A solvent that is resistant to fluctuations in pH, because it is made with a combination of weak acid and its conjugate bases. Acid A chemical substance that neutralizes alkalis, dissolves some metals, and turns litmus red; typically, a corrosive or sour-tasting liquid of this kind. Base A substance capable of reacting with an acid to form a salt and water, or (more broadly) of accepting or neutralizing hydrogen ions. Genomic DNA Digestion The cleaving of linear DNA; for example- in genomic DNA when three cuts are made with a restriction enzyme four fragments result. Plasmid DNA Digestion The cleaving of circular DNA; for example- in plasmid DNA when three cuts are made with a restriction enzyme three fragments result. Kilo- 10^3 Ex. 1 kiloliter (kL) = 1000 liters (L) Milli- 10^-3 Ex. 1 molar (M) = 1000 mM Micro- 10^-6 Ex. 1 gram (g) = 1,000,000 micrograms (ug) Loading Dye A solution added to an electrophoresis sample to give it color and density; 1 microliter is added for every 5 milliliters of sample. Agarose A polysaccharide, generally extracted from certain red seaweed, used to make gels for DNA electrophoresis. pH Scale Measures how acidic or basic a substance is; ranges from 0 to 14; logarithmic scale- ex. pH 4 to pH 2.. pH 2 is 100 times more acidic. Significant Figures Each of the digits of a number that are used to express it to the required degree of accuracy, starting from the first nonzero digit; all non zero digits are significant; leading zeros (0.002) are not significant; captive zeros (1001) are significant; trailing zeros (100 or 100.0) are only significant if a decimal is present anywhere within the measurement. Spectrophotometry Used to determine the amount, or concentration, of a protein (or other substance) present in a sample by measuring how much it absorbs light as it passes through the sample solution. Occupational Safety & Health Administration (OSHA) Government agency that examines workplace conditions to ensure safety. Safety Data Sheet (SDS) Document that provides comprehensive information about a substance or mixture for use in workplace chemical management. Personal Protective Equipment (PPE) Equipment worn to minimize exposure to a variety of hazards. Independent Variable Variable that represents inputs or causes and is controlled by the experimenter. Dependent Variable Variable that represents the output or outcome whose variation is being studied; measurement. Gloves Required Electrical/High Voltage Corrosive Biohazard Harmful/Irritant Eye Wash Station Location Radiation Hazard Goggles Required Oxidizer No Eating/Drinking Dilution Formula C1V1=C2V2; 1's represent the stock (initial) solution and 2's represent the dilute (final) solution. Mass Percentage (w/v) Formula % = [(mass of solute in grams)/(volume of solution in mL)] x 100 Volume Percentage (v/v) Formula % = [(volume of solute in mL)/(volume of solution in mL)] x 100 Analytical Balance Used to measure mass. Autoclave Used to sterilize media, trash, and supplies by reaching the correct temperature and pressure. pH Meter Used to measure acidity or alkalinity of a solution. Centrifuge Used to separate substances based on density. Vortexer Used to mix small volumes of solution. Shaking Incubator Used to mix cultures at a constant temperature. Thermal Cycler (Thermocycler) Used to amplify DNA by heating and cooling. Micropipette A laboratory instrument used to measure, dispense, and transfer very small amounts of liquid. Serological Pipette Used to measure and deliver large volumes of liquids. Serial Dilution Stepwise dilution of a substance in solution. Concentration A measurement of how much solute exists within a certain volume of solvent. Absorbance The capacity of a substance to absorb electromagnetic waves (as light). Erlenmeyer Flask A conical, flat-bottomed laboratory flask with a narrow neck. Beaker An open cylindrical container with a pouring lip; used for mixing larger amounts of substances. Volumetric Flask Holds chemicals during mixing and storage; used for accurate measurement of a specific volume. Graduated Cyclinder A tool used to measure the volume of a liquid. Media Bottle Container used to store agar, broth, chemicals, etc. Microcentrifuge Tube Includes a snap cap, and holds small volumes of liquid. Incubator An apparatus or chamber that provides favorable environmental conditions (temperature) for the growth of cultures. Streaking for Isolation Method of streaking bacteria to grow individual colonies. Density Formula Density (D) = Mass (m) / Volume (V) Weigh Boat Tray used to weigh or transfer chemicals (usually dry). Conical Tube Capped tube used to hold chemical substances. Scoopula/Spatula Used to transfer small amounts of solid chemicals. Microscope Device that produces magnified images of structures that are too small to see with the unaided eye. Waterbath Used to incubate samples in water at a constant temperature over a long period of time. Electrophoresis Power Supply Connects to an electrophoresis tank setting up an electric field between the two electrodes. Stir Plate Device used with a magnetic stir bar to provide stirring action in a liquid. Hot Plate A lab tool used to heat substances. Agar A gel-like polysaccharide compound used for culturing microbes; extracted from certain red algae. Aseptic Technique A sanitation practice performed with a goal of minimizing contamination by pathogens. Health Hazard Acute Toxicity Environmental Explosive Compressed Gas Meniscus The curve at a liquid's surface by which you measure the volume of the liquid. Solute A substance that is dissolved in a solution. Solvent A liquid substance capable of dissolving other substances. Solution A homogeneous mixture of two or more substances; mixture that forms when one substance dissolves another.