Mechanism 4 shows the debromination of 2α-bromocholestan-3-one to give 4. This mechanism which is similar to a Favoskii rearrangement‚ is likely to go via this path as other research has shown that there is often a by-product with this reaction. The by-product is cholest-4-en-3-one which requires the intermediate seen in the third molecule in the above mechanism. The intermediate is highly strained and with the presence of base a proton will be extracted which aids the collapse of the three membered
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Communication‚ Homeostasis & Energy Communication & Homeostasis Outline the need for communication systems within multicellular organisms‚ with reference to the need to respond to changes in the internal and external environment and to co-ordinate the activities of different organs. Organisms need to respond to external stimuli‚ e.g. temperature‚ oxygen concentration and levels of sunlight. These may be over time‚ e.g. winter fur to summer fur‚ or quickly‚ e.g. changing size of pupils. Internal
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#32 One medium suitcase If I was leaving home‚ and I could only pack what would fit inside a medium suitcase‚ the first thing I would pack would be my cell phone‚ and charger. These are essential because what if something happens to me. How am I supposed to get in touch with people? The next thing I would pack is money and credit cards. These are very important because if I can’t fit clothes I can purchase my own. The next items are tooth brush and brush I cannot have knots and hair everywhere
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BIO 353 Cell Biology Study Questions for Exam #3 Fall‚ 2012 Cytoskeleton “The harder the conflict‚ the more glorious the triumph.” Thomas Paine... “Unless you really just screw up.” Bush 1. What are microfilaments? (He said know how to identify/draw these) Note: since it is multiple choice‚ I doubt we will have to know how to draw them. **There are also short essay questions and‚ in past classes‚ he has asked students to draw. I thought the final was ALL MULTIPLE CHOICE???********************************
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AP Chemistry Dr. Istone Lab 3: Gravimetric Analysis of a Metal Carbonate Lab Objective: In this lab we will determine the identity of a group 1 metal carbonate compound by gravimetric analysis. The unknown is weighed and dissolved in water and the precipitate is filtered‚ dried‚ and weighed. From the data the formula weight and identity of the unknown metal carbonate is determined. Lab Procedure: 1. Set up the Bunsen burner and ring clamp‚ light the burner and heat the crucible
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High School Biology - Core Concept Master Cheat Sheet Biology‚ 1 of 6 01: The Science of Biology 03: The Cell • Characeristics of life Organization: all lives are well organized Energy use: all lives need energy to support Reproduction: all lives should be able to reproduce itself Growth: all lives grow and develop. Response to stimuli: all lives can respond to internal or external stimuli Homeostasis: all lives have the ability to maintain a relatively stable internal environment—self-regulation
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Introduction: Rennin is usually present in out stomach it helps us digest protein. Enzymes have optimum temperatures‚ since rennin is an enzyme from the human stomach its optimum temperature would be around 37-38 Celsius‚ optimum pH would be 1-3. If the temperature is too low the enzymes will move around slowly. A temperature that is too high or an incorrect pH would denature the enzyme. Materials: 25 rennin labels Beaker (400 ml) Ice bath 25 test tubes Funnel Cheese cloth Milk
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Substitute lab for Unit 6 lesson 3: Stoichiometry: Counting by Measuring Mass Purpose Determine the mass of several samples of chemical elements and compounds and use the data to count atoms. Procedure Start Virtual ChemLab and select Counting by Measuring Mass from the list of assignments. The lab will open in the Calorimetry laboratory. Part 1‚ Measuring Metal 1. Click on the Stockroom. Click on the Metals sample cabinet. Open the top drawer by clicking on it. When you open the drawer‚ a
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1.CANCER Cancer /ˈkænsər/‚ known medically as a malignant neoplasm‚ is a broad group of diseases involving unregulated cell growth. In cancer‚ cellsdivide and grow uncontrollably‚ forming malignant tumors‚ and invading nearby parts of the body. The cancer may also spread to more distant parts of the body through the lymphatic system or bloodstream. Not all tumors are cancerous; benign tumors do not invade neighboring tissues and do not spread throughout
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visible to the predators. Knowing that we started with 30 of each of white and yellow “paper moths” in the simulation‚ and considering the numbers your hunters picked up‚ how many of each type of paper moths survived after each trail: Trail One: 3 White Paper Moth & 9 Yellow Paper Moth Trail Two: 4 White Paper Month & 7 Yellow Paper Moth Trail Three: 13 White Paper Moth & 18 Yellow Paper Moth What did the experiment show about how prey are selected by predators? This experiment showed that
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