please do it

Contribute to Content Discovery: EITHER Respiration OR Photosynthesis Choose a topic from either the respiration or photosynthesis PowerPoint presentations. (Post due Friday, reply due Tuesday) Instructions: Go online and look up content related to the assigned module. It can be videos or tutorials that help explain terms and concepts covered. It can be interesting podcasts, videos or articles that show the relevance or application of material covered in the module. Post a link to the website you find and give a short summary of between 100 to 200 words. PowerPoint presentation REPLACEMENT AT-HOME BIOMOLECULES LAB Introduction: There are four major classes of macromolecules that make up living things: Carbohydrates, Lipids, Proteins and nucleic acids. Look over the Biomolecules Lab readings on the HOL page for details of each of these kinds of macromolecules. There are also plenty of good videos on this subject. You would have done some variation of the following tests if you used the HOL lab kits: 1. A test for simple sugars like monosaccharides and a few disaccharides using Benedicts reagent, which starts off light blue in color. The Benedicts reagent turns red, orange or yellow when heated (in boiling water) in the presence of simple sugars. 2. A test for starch using iodine. A few drops of an iodine solution are added to a sample. Iodine turns dark blue or black if starch is in the test sample. Otherwise the iodine remains it’s normal, brown color. Sometimes you need to dilute the iodine if it’s too dark so you can tell brown from blue/black. 3. A test for lipids using Sudan III. The Sudan III dissolves in lipids. The unknown sample is applied to a paper filter spotted with Sudan III. If the red Sudan III runs along the filter with the spreading sample, then lipids are present. A simpler way to test for lipids is to look for the presence of a grease spot on brown paper when a sample containing lipids is applied to the paper. 4. A test for proteins using Biuret reagent. Biuret reagent is light blue but turns light purple in the presence of proteins. Look over the HOL instructional manual to get an understanding of the background for this lab. A quick Google search on the Benedicts test, Biuret test, iodine test for starch and testing lipids using Sudan dyes will also give you a good idea about testing for these macromolecules. We will only be doing the iodine test for starch and the brown paper test for lipids. Feel free to try the Benedicts test, Biuret tests and other tests if you get your kits on time. The tests are not hard and you have the materials anyway. So you might as well play around. I will only grade you for the procedures below. Here is a quick summary of the test you will do for lipids: Rub food onto some brown paper. If it leaves a grease spot, then lipids are present. Give the spot time to dry before writing down your results. Even water will leave a dark spot before it dries. Here is a quick summary of the iodine test you will do: Add a drop of iodine to the food you are testing. Starch is present if the iodine turns blue or black. You may need to dilute the iodine if it is already dark when you buy it. Materials: Tincture of Iodine. This can be purchased from Walgreens or other similar store. A one-ounce bottle costs about $6. Povidone iodine works too. DO NOT USE DECOLORIZED IODINE! Brown paper. As from a brown paper shopping bag, butcher paper or brown paper napkins. Various foods that you think may contain lipids and starch: Find three foods that contain starch and three that do not. Find three foods that contain lipids and three that do not. Lipid Test Method: 1. Collect numerous foods that may or may not contain lipids (fats or oils). I strongly suggest one of your foods be water (because you know it does not contain lipids) and another be butter or vegetable oil (because you know they do). 2. Rub each food (it can be solid or liquid) into the brown paper and let it dry. Water should star off leaving a dark spot and become lighter as it dries. A dark spot from butter or oil should remain dark. 3. Do this until you have three foods that tested positive for lipids and three that tested negative. List the lipid test results for these foods in the table below. Lipids will leave grease spots even after they dry. Starch Test Method: 1. Collect numerous foods that may or may not contain starch. I strongly suggest one of your foods be water (because you know it does not contain starch) and another be white bread or potato (because they should contain starch). 2. Apply a drop of iodine to the (solid or liquid) food. If it is liquid, then pour some into a cup. You may want to dilute the iodine in water until it appears light brown if it is too dark in its original bottle. 3. Do this until you have three foods that tested positive for starch and three that tested negative. List the iodine test results for these foods in the table below. BIOMOLECULES LAB WORKSHEET Name____________ Table 1. Lipid Test for various foods Food Tested Color Presence of Lipids (+ or -) Table 2. Iodine Test for various foods Food Tested Color Presence of Starch (+ or -) Summary of Results: 1. Summarize your results in your own words. If anything did not go as expected then explain what you think caused this to happen.