2.5 % Light Transmittance Associated with Various Concentrations of Dye Dye Solution % Concentration of Dye % Light Transmittance 1 0 (DH2O only) 100 2 10 3 25 4 75 5 100 (stock) Unknown A, B, C, D (circle yours) What relationship exists between concentration of dye and % transmittance? Part C2: The Standard Curve Procedure Plot the 0%, 10%, 25%, 75%, and 100% data from Table 2.5 on Fig. 2.2 Attempt to draw a “best fit” line through the scatter of data points. Do not simply connect the dots. Make your line pass through the “average” spread of the dots. This line represents a standard curve and illustrates the relationship between percent concentration of a dye solution and percentage of light transmitted. Use this standard curve to complete Part C3
Materials Equipment test tubes and racks 10 ml pipettes pipette pumps 10 ml graduated cylinders marking pencils (Sharpie) filter paper disks Petri dish water baths at 95C Reagents and Solutions 1% dextrose (glucose) 6% starch (amylose) 1 M NaOH juice chicken broth egg milk vegetable oil distilled water Benedict’s IKI Biuret Sudan IV Part A: Detection of Carbohydrates Carbohydrates are molecules consisting of one (monosaccharide), two (disaccharide), or many (polysaccharide) simple sugars. Examples of carbohydrates include glucose, sucrose, glycogen, maltose, and starch (amylose). In this exercise, you will experiment with two carbohydrate reagents: Benedict’s reagent – usually light blue in color, forms a yellow-green, orange, or red precipitate when boiled in the presence of reducing sugars such as simple sugars (e.g. glucose) Iodine-Potassium Iodide (IKI) – amber colored, forms a dark purple or black precipitate in the presence of starch. Read the information on the following (Parts A1, A2, and A3) and fill in the first three columns of Table 3.2 before performing the experiments. Part A1: Detection of Simple Sugars Procedure Obtain a test tube rack and six test tubes per group Label the test tubes 1 through 6. #1 and #2 will be used in this part Use a 10 ml pipette to transfer 1 ml of the dextrose (glucose) solution to test tube #1 Use a different (why?) pipette to transfer 1 ml of the starch solution to mix before transferring) to test #2 Use a 10 ml graduated cylinder to measure and transfer 1 ml of Benedict’s reagent to each test tube. Swirl to mix Note the color of each solution Gently heat the contents of each test tube in a 95C water bath for two minutes Observe and record any change in Table 3.2 Part A2: Detection of Starch Procedure Use a pipette to transfer 1 ml of dextrose solution to test tube #3
FADH2 ATP How many ATPS are produced during glycolysis glycolysis (net) Krebs cycle aerobic respiration (eukaryotes) anaerobic respiration (net) Some wines are marketed as “sparkling” wines. Sparkling wines are considered so due to a dissolved gas that makes them fizzy. Apply what you know about the process of respiration to explain the type and origin of this gas. Animals are either homeothermic or poikilothermic (homeo – same, poikilo – varied, thermic – warm), more commonly known as “warm-blooded” or “cold-blooded”, respectively. Homeothermic animals include mammals and birds. Examples of poikilothermic species would include the invertebrates, reptiles, fish, amphibians, etc. Using what you have learned about respiration and enzymes, explain why poikilotherms move more slowly in the winter than the summer.
Practice Problems and Review Questions Define or describe the following: DNA STR PCR locus (loci) annealing In DNA, __________ binds to thymine, guanine binds to __________ through __________ bonds. How many loci are required by the FBI to positively identify an individual? Is it reasonably possible for two, non-related persons to share the same genotypes at all these loci? Why or why not?
#2 (a & b) Since it can reasonably be assumed that distilled water does not contain lipids or proteins it makes a perfect control. Notice it is distilled water and not tap water. Tap water contains many other things and would not make a good control. Distilled water is just water, nothing else. #3 Test Substance Reagent Test Procedure Color of Positive Result Color of Negative Result Starch IKI 1 drop dark blue / black Amber Sugar Benedict’s 1 ml red, orange, green, yellow Blue Lipid Sudan IV Soak 3 mins pink / red no color or very light pink Protein Biuret 1 ml NaOH, 0.5 ml reagent violet no change #4 The IKI test must be performed first. If a Benedict's is done first, the heat will hydrolyze any starch present and it will go undetected. #5 They differ in number of monomers. Monosaccharides, like glucose, consist of one monomer. Two saccharide monomers (for example sucrose which is made up of a glucose and a fructose monosaccharide), would be a disaccharide. Oligosaccharides are typically three to ten monosaccharides long. Polysaccharides are typically >10 monosaccharides (for example, starch and glycogen). #6 Glycerol and palmitic (fatty acids) #7 Amino acids #8 Primary - of the amino acids in the protein. Secondary - a protein's "orientation in space"; evident as either an α helix (spiral) or ß sheet. Tertiary - protein folding back on itself due to chemical interactions among the amino acid side (or "R") groups. Quaternary - occurs when two or more