Reference no: EM132477861

SCH1111 - Fundamental Biomedical Techniques - Edith Cowan University

MICROSCOPY - THE STANDARD COMPOUND MICROSCOPE

Activity: Using a compound light microscope. As you work your way through the following activity, please label the image.

Question 1.    Convert the following to required units and write in scientific notation. Follow this example:

25 kg = 25x10⁹ µg, or written in scientific notation 2.5x10¹⁰ µg.

Now you do the rest.

a)  75 mL =                  L

b)  0.01 mg =                  ng

c)  50 g =                    µg

d)  0.05 ng  =                     g

e)   0.05 g =                      ng

f)       800 µl =                       mL

g)      500 mL =                      µl

h)      7.5 mg =                        µg

i)          93 µg =                      g

Question 2. If I have a stock solution of 20 g/L and I wish to make a more dilute working solution that has a final concentration of 20mg/mL how much of the original stock solution should I use to make a final volume of 50mL of my working solution.

Question 3. Calculate the concentration of the final solution if I take 5mL of my stock solution which has a concentration of 50g/L and I dilute it to a final volume of 500mL.

Question 4.  What is the concentration of the original stock solution if I take 5 mL of my stock and dilute it to 5 µg /mL in a total volume of 50mL.

Question 5. Calculate the amount of NaCl I would need to make a 25% (w/v) solution in water.

Question 6. Calculate the volume of lactic acid I would need to make a 15% (v/v) solution with water.

Question 7.    Work out the amount of alcohol I would need to add to a 2:8 solution of chloroform with alcohol in a total volume of 80mL.

Question 8. Is 50ug/µl the same as 50g/L?

Question 9. Is 100 g/mL the same as 100 mg/µl?

Question 10. Is 75 kg/L the same as 75 µg/µl?

Question 11. Write 8.3 X10 ⁵ in decimal form.

Question 12. Write 0.00003 in scientific notation.

Question 13. 3.5 x 10 ⁴ x 3.5 x 10 ^-3 =

Question 14. 6.2 x 10 ⁵ + 2.7 x 10 ⁵ =

Question 15. 45 x 10 ⁴ / 9 x 10 ⁴ =

Question 16. 75 x 10 ^{- 4} x 0.003 x 10 ⁷ =

Activity: MAKING A 6% SODIUM DIHYDROGEN PHOSPHATE (W/V)

Activity: MAKING 2% (V/V) HYDROCHLORIC ACID

Question 1. 1XTBE buffer contains 10.80g Tris, 5.50g boric acid, 0.744g EDTA per litre of solution.

a) How much of each of these ingredients are required to make 1 litre of 10XTBE stock solution?

b) Describe how you would make 10 litres 10XTBE.

Question 2. A litre of 6% (w/v) stock acrylamide solution (used in acrylamide electrophoresis gels) contains 57g acrylamide, 3g bisacrylamide, 420g urea dissolved in water. What weights of these ingredients are required for a litre of 4% stock acrylamide solution?

Question 3. 10X PBS (phosphate buffered saline) contains 80.0g NaCl, 14.4g anhydrous Na2HPO4, 2.4g KH2PO4, and 2.0g KCl.

a) How do you make 10 litres of 10X PBS?

b) How do you make 1 litre of working (1X) PBS buffer from the 10X PBS stock?

c) How do you make 1 litre of 1X PBS solution?

Question 1. What concentration of solution would I have if I took 10mL of a 1M solution and added 50 mL of water to it?

Question 2. How much NaCl would I need to weigh out to make 10 mL of a 10 0mM (millimolar = millimoles per litre) solution?

[Molecular weight of NaCl is 58.5]

Question 3. A 10M solution (10 molar solution) contains 10 moles of solute per litre. How many moles are there per mL?

Question 4. Can I write 15M solution as 15mmoles / L or 15mmoles /mL?

Question 5. Write 5.8 g as mg; and as ng.

Question 6. 2.5mg/mL is 2.5ng/nL - true or false?

Question 7. Write 123456.7 in scientific notation.

Question 8. If I have 10mL of a 7.5 mM solution, what volume did I take from a 10M stock solution to make this solution?

Question 9. Calculate 0.000050 x 0.050 and write in scientific notation.

Question 10. If I have 234 mg of NaCl in 20 mL, what is the concentration of this solution in

a. g/L

b. mg/L

c. moles /L

d. mmoles /L?

MOLE AND MOLARITY PRACTICE

Question 1. What is the mass of 1 mole of carbon dioxide (CO2)?

Question 2. How many atoms of carbon are there in 1 mole of carbon dioxide?

Question 3. How many atoms of oxygen are there in 1 mole of carbon dioxide?

Question 4. How many molecules in 10 moles of water?

Question 5. How many atoms in 10 moles of water?

Question 6. How many atoms in 1.5 moles of calcium?

Question 7. How many ions in 2 moles of sodium chloride?

Question 8. How many positive ions in 2 moles of sodium chloride (Na⁺Cl^-)?

Question 9. How many negative ions in 3 moles of aluminium chloride (AlCl3)

Question 10. What is the molar mass of nitrogen gas (N2)?

Question 11. What is the molar mass of helium gas (He)?

Question 12. What is the molar mass of magnesium oxide (MgO)?

Question 13. What is the molar mass of ethanol (C2H5OH)?

Question 14. How many moles are present in 9g of water (H2O)?

Question 15.  How many moles are present in 117g of sodium chloride (NaCl)?

Question 16. How many moles are present in 2.4g of carbon?

Question 17. How many moles of sodium iodide (NaI) are dissolved in 0.5L of a 1M solution?

Question 18.How many moles of NaI are dissolved in 100mL of a 0.1M solution?

Question 19.

Ar: Na = 23 amu Cl = 35.5 amu

A NaCl saline solution is 9% (w/v). What is its molarity?

Question 20. Which contains the most NaCl: 250mL of 0.01M NaCl solution; or 20mL of a 0.15M NaCl solution?

BUFFERS

Answer these questions to help you to develop your discussion and conclusion:

Question 1. How many acid drops was required to add to ddH2O to see the change in pH?

Question 2. How many drops of alkali were required to add to ddH2O to see the change in pH?

Question 3. How many drops of hydrochloric acid were added to a buffer before pH dropped?

Question 4. How many drops of sodium hydroxide were added to a buffer before pH rose?

Question 5. Have you successfully demonstrated the buffering capacity of the Na2HPO4-NaH2PO4 buffer?

Question 6. What did you learn about buffers?

Question 7. Don't just write the answers to these questions, they should be included in the text of your discussion.

Question 1. What volume of solution should I take to make 10mL of a 1M solution from a stock solution of 10M?

Question 2. How much NaCl would I need to weigh out to make 100mL of a 5mM (millimolar = millimoles per litre) solution?

[Molecular weight of NaCl is 58.5]

Question 3. If I have a 5M solution of NaCl, how many moles are there per L and per mL? If I take 1mL, what is the concentration of the solution in the 1mL?

Question 4. Can I write 5 mM solution as 5 mmoles / L, or 5 mmoles /mL?

Question 5. How many mg do I need to weigh out to get 75g?

Question 6. 80µg/µl is the same as: 80ng/nL - true?

80g/L - true?

80g/mL - true?

Question 7. Write 31415926535893238 in scientific notation.

Question 8. I need to make 10mL of a solution of 20% (w/V) NaCl. What is the concentration of this solution in moles/L (or M)?

Question 9. If I have a 46.8 % solution of NaCl; what is the concentration of this solution in: g/L

SPECTROPHOTOMETRY

Question 1: A 1.0 mM solution of a compound gives an A340 of 0.6. Calculate the molar extinction coefficient using A = ? ? [C] assuming that the solution is in a 1cm tube.

? = molar extinction coefficient;

? = length or thickness of the tube (in cm); [C] = molar concentration of the solute.

Question 2. A student measures the absorbance of a solution at different concentrations. Plot the results and determine the unknown concentration of the solution at an absorbance of 0.750.

Concentration	Absorbance at 720 nm
0.08M	0.25
0.16M	0.4
0.24M	0.6
0.32M	0.8
0.4M	1

Question 3. What will happen if a student handles the cuvette and leaves fingerprints on the surface? How will the measurement be affected?

Discussion and conclusion

Answer these questions to help you to develop your discussion and conclusion:

Question 1.  Do the absorbances that the spectrophotometer delivers indicate the same colours that your eyes see?

Question 2. Does your chosen colour obey Beer's law?

Question 3. Can you calculate a molar extinction co-efficient for your chosen solution (assuming the length of the tube is 10 mm?

SPOTS BEFORE MY EYES

In this example you will have calculated a series of dilutions from 100 -> 10-5 and a series of dilution factors for 100 -> 105.

Question 1. What is the maximum number of colonies that you could count on an agar plate?

Question 2. What should you do if the colonies are starting to overlap on the plate surface (rather than seeing clear individual colonies?

Question 3. If you had the following results from Plates 1 - 6, how would you calculate the population of the undiluted stock?

Plate 1	Plate 2	Plate 3	Plate 4	Plate 5	Plate 6
TNTC	TNTC	289	26	2	1

TNTC = Too numerous to count

Question 4. What could you do to make this population estimate more accurate?

Review questions:

Question 1. What types of experiments might require a gel to be run?

Question 2. What other types of gels can be run in the laboratory?

Question 3. What do the following procedures test for?

a. Northern Blot

b.Southern Blot

c. Western Blot

Question 4. What components do you need to perform a polymerase chain reaction?

Question 5. You are setting up a PCR reaction to detect Mycobacterium tuberculosis in a sputum sample from a patient. How should you treat the patient sample to allow PCR analysis to be performed?

Question 6. You have been given the forward and reverse primer stock solutions which are at a concentration of 400 µM. You need the primers to be at a working concentration of 10 µM. How would you make up the working solution?

Question 7. In the final PCR mixture, you use 1 µL of each primer working stock in a final volume of 20 µL. What is the final working concentration of primer?

Question 8. You run a PCR and get the following result. The product should be 520 Kb. Does the patient have TB?

Attachment:- Fundamental Biomedical Techniques.rar