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1、Day 1: Find it, Do it, Teach It!* Perform each of the 9 basic lab tasks from start to finish * Focus on the steps to complete tasks * Document the steps for developing teaching protocols and assessment, including a rubric as appropriate. The assessment should include both group and individual accoun
2、tability, and a specific set of questions or measurements to assess performance (How do you know if theyre doing it right? How do you know if theyre learning what you want them to learn?) * Prepare one complete protocol and assessment presentation with images and Power Point instructions.Exercises:
3、1. pH: using standardized meter, identify pH of unknown; make 1M citrate solution, adjust to 6.5; using Internet - find what buffer is used for; how to standardize, clean probe, how to drop (adjust) the acid/base 2. Molarity: make 100ml of 0.5 M NaCl solution 3. Percent solutions: make 100 ml 70% Et
4、OH from pure EtOH and Reagent grade 4. Gels: prepare 50 ml 1% agarose and pour gel 5. Microbiological media: make 200 ml LB broth (from scratch), then make 100 ml LB agar 6. Complex buffer: citrate (.3M) + sodium chloride (0.1M), make 100 ml 7. Pipetting: w/ bulb, micropipette, etc: low volume, blue
5、, yellow, w/ plug, pipette aid/bulbs + serological. 8. Dilution series: volumetric and pipette skills. Going from 0.5 M to 0.1 M to 0.01, 0.001 9. Think Station#1 PHProtocol1. Each group should calibrate the pH meter using the pH=7.0 and 4.0 standards. 2. Each group should then titrate the citric ac
6、id solution supplied to them. 3. Each group should estimate the pH of the three mystery solutions.For 1. Follow the instructions on the pH meter to calibrate the meter.For 2. Test the pH of the citric acid in the numbered tube. Gradually add NaOH, by drop, checking the pH as you go, until you reach
7、a pH of 6.5. If you overshoot 6.5 dont panic. Stop doing the exercise and record the pH. If you did overshoot how would you bring the pH back down?For 3. Determine the pH of the unknowns by simply placing the probe in each of the three mystery solutions.Additional: There are pH strips and handheld p
8、H meters also on the bench. PLAY! #2 MOLARITY1) Materials a) Distilled water, NaCl, beaker, graduated cylinder, stirring rod/electric stirrer, label tape, marker, scoopula, disposable pipette, balance. 2) Find the molar weight of the NaCl from its chemical formula 3) Use the definition of M (molarit
9、y) to calculate the moles of salt needed to make the specified solution. 4) Convert moles of salt needed to mass of salt 5) Now prepare 50 ml of the 0.5 M salt solution. a) Put a weighing paper on the electronic balance b) Tare the balance c) Measure out the calculated mass of salt on the weighing p
10、aper d) Add the salt to the graduated cylinder. e) Add distilled water to the graduated cylinder to a bit below the required volume. Try to wash down any salt that may have stuck to the inner wall of the graduated cylinder f)Mix well with stirring device. g) Top off the solution to the required volu
11、me mark, using level sighting to prevent parallax error, using a disposable pipette. 6) Label the prepared solution in a 50 ml conical tube.#3 Percent SolutionsMaterials: Graduated cyclinder, parafilm, 95% ethanol, distilled water, pure ethanol (100%)Make 50 mL of 70% EtOH solution from pure EtOH (1
12、00%). Make in graduated cyclinder. Use parafilm over top of graduated cyclinder to allow mixing. Place finished solution in 50 mL conical tube and label clearly.Make 50 mL of 70 % EtOH solution from reagant EtOH (95 % pure). Make in graduated cyclinder. Use parafilm over top of graduated cyclinder t
13、o allow mixing. Place finished solution in 50 mL conical tube and label clearly.Be clear about volumes you are using.#4 Making an agarose gelPreparation and pouring of a 1% agarose gel 1. Review the definition of a percent solution. 2. Calculate the grams of agarose needed in 50ml of 1X TBE to make
14、a 1% agarose solution. 3. Place a plastic weigh-boat on an electronic balance, and rezero the balance. 4. Measure the amount of agarose calculated from step 1 into the weigh-boat using a clean spatula. 5. Place the measured agarose into a clean 250ml beaker, and add distilled water until a volume of
15、 50ml is obtained. 6. Place the agarose solution onto a hot plate, and heat until agarose is fully dissolved. Do not allow the agarose to boil. 7. Remove the heated agarose solution, and swirl to insure agarose distribution. 8. Place label tape around the open edges of an empty gel electrophoresis t
16、ray. Firmly press the edges of the tapes onto the bottom and sides of the tray to discourage leakage. 9. Place plastic combs in the notches at the edge of the tray. 10. Allow the agarose solution to cool to about 60 degrees C, or until the beaker can be held in your hand. An agarose solution above this temperature will cause leakage from the gel tray. 11. Pour the heated agarose solution in the tray, watching carefull
