Transcript File
The Student will learn how to use indicator solutions and standards to test for the presence of biologically important molecules such as; simple sugar or monosaccharide, carbohydrate or polysaccharide, lipids (fat), and protein. We will use an egg as a representation of a cell . The shell is a protective outer covering to prevent the embryo from damage and must be carefully removed in order to look closer at the “cell” components. After placing the egg in an acetic acid solution (CH3COOH or 5% - white vinegar) overnight, what type of chemical reaction has occurred? CaCO3 + 2 CH3COOH CO 2 + Ca(CH3COO)2 + H2O Is this a balanced equation? What do we add to balance the equation? Separating the egg into its components is called fractionation. What are the components of the “cell” egg? ◦ ◦ ◦ ◦ Calcium carbonate shell Plasma membrane Cytoplasm – egg white Nuclear membrane and nucleus – egg yolk FRACTIONATION Testing components with indicators must be compared against known composition standards, (also called positive controls) with respect to indicator solutions. ◦ pH change of phenol red to yellow indicates the presence of carbon dioxide STANDARDS Glucose (Simple Sugar C6H12O6 Monosaccharide) Starch (Complex Sugar or Polysaccharide) Protein (very large molecule or macromolecule made up of amino acid chains containing C, H, O, and N) Fat (one type of Lipid) Molecule Tested Benedict’s Solution Lugol’s Iodine Biuret Reagant Paper Bag test or Sudan IV Indicator used Definitions: air cell - an empty space located at the large end of the egg; it is between the inner and outer shell membranes. chalaza - a spiral, rope-like strand that anchors the yolk in the thick egg white. There are two chalazae anchoring each yolk, one on the top and one on the bottom. (The plural of chalaza is chalazae.) germinal disc or blastodisc - a small, circular, white spot (2-3 mm across) on the surface of the yolk; it is where the sperm enters the egg. The nucleus of the egg is in the blastodisc. inner shell membrane - the thin membrane located between the outer shell membrane and the albumin. outer shell membrane - the thin membrane located just inside the shell. shell - the hard, protective coating of the egg. It is semi-permeable; it lets gas exchange occur, but keeps other substances from entering the egg. The shell is made of calcium carbonate. thick albumin - the stringy part of the egg white (albumin) located nearest the yolk. thin albumin - the watery part of the egg white (albumin) located farthest from the yolk. vitelline (yolk) membrane - the membrane that surrounds the yolk. yolk - the yellow, inner part of the egg where the embryo will form. The yolk contains the food that will nourish the embryo as it grows. STANDARD (Molecule Tested) Egg Membrane Yolk (Egg Yolk) Egg White Glucose Yes / No Yes / No Yes / No Starch Yes / No Yes / No Yes / No Protein Yes / No Yes / No Yes / No Fat Yes / No Yes / No Yes / No Only black ink on all entries into the notebook Added papers must be taped on all four sides ◦ NWUI written on the bottom right corner ◦ Initialed ◦ Dated Any incorrect entries must be single lined out ◦ Single lined out ◦ Initialed ◦ Dated Page 1 Advanced Biotechnology Notebook Cedar Ridge High School Your full name Today’s Date Write “Table of Contents” at the top of each of these pages Both facing (left) and frontage (right) pages will be used The first page of every lab investigation should be listed and fully titled in the Table of Contents Sign and date the bottom center of every page starting on page 6 as you fill the page On the bottom center of the page you will write “go to page ____” At the top corner, outside of the next page starting on page 7 you will write “from page ____” Never write any laboratory information on the last three lines of the page On the last line of the page remember to sign and date the bottom center of every page starting on page 6 as you fill the page On the bottom right of the page, starting on page 6, you will write “go to page ____” At the top left-hand side of the next page, starting on page 7, you will write “from page ____” Heading at the top of a new page to include: A short description of the purpose of the lab: ◦ Name of lab ◦ Date of lab ◦ Full name of student ◦ This may be done as an objective, purpose, assay Safety specifics for the lab (general safety is understood) Materials and Equipment list Detailed list of Steps or your SOP in your own words leaving a full space in between each numbered step. (You may type and print pre-lab information but you must follow proper taping instructions.) Re-write allows for familiarization of procedures preventing mistakes and wasted time. Materials list should be present prior to instructions. Record all directions and steps for procedures. All quantities should be specifically listed. All numbers must have units. Lines must be skipped between all sections and data tables, graphs, and important statements or conclusions. Qualitative data along with Quantitative data must be recorded. You must use sufficient clarity that someone else with similar skills can repeat your procedures if necessary. Only universally accepted standard abbreviations may be used. Write pre-labs only on the left page (facing) only Right pages (frontage) will be used for recorded notes , data, results during lab. If your pre-lab is typed you must format it to fit the page and have no paper hanging over the edges after taping. The SOP should have only information limited to the lab and should not include the additional information such as background or history that handouts will have. This additional information is there to assist you in the learning of material or techniques and should not be included on the pre-lab. (Extract only actions required out of the material.) Pre-labs will be checked off just as your supervisor in a work place will check your procedures. During lab you will write everything down in black ink to the right of the procedures. This includes supply lots on reagent containers, dates opened, what balance you used, time frames including intermittent times, etc. Changes that are made to the procedure need to be documented and always, ALWAYS, show calculations and units. This documentation may be proof to where something went wrong or possibly a link to a new discovery. Each team member will write their own notes and data but include their name in your report. At the end of the report, after the conclusion, you must list all persons from whom samples or data were obtained and included in your report. Any critical entries such as key data, analysis conclusions, or new ideas must have a “coworker” sign and date the entry in blue ink. However, they must not be involved directly in your data gathering or a co-inventor of your procedure but capable of understanding the meaning of the notebook entry. Glassware, sharp objects, mild acid, eye protection, clothing protection, hand protection, do not ingest, caution near heat MSDS cautions for: ◦ Benedict’s Solution ◦ Lugol’s Iodine Solution ◦ Biuret reagent (10%NaOH and CuSO4·5H2O) Check the NFPA for Health and Fire Safety http://avogadro.chem.iastate.edu/MSDS/BenQSol.pdf http://www.sciencelab.com/msds.php?msdsId=9924378 http://www.stmarytx.edu/environmentalhealth/pdf/biology/Flinn/BiuretTestSolutionFlinn.pdf