Wednesday, March 12, 2008

Introduction to Biochemistry Laboratory Manual


Skill Building Exercises, Guided Experiments, and Open Inquiry Experiments
Below is a summary of each experiment type you will perform and expectations for each.

Skill-Building Laboratories : Skill-building labs are designed to help you learn the techniques you will need for that entire section of the lab manual. You will be given step-by-step directions how to perform each technique, including pictures of instruments you will use. Thus, it is very important that you pay particular attention in skill building labs. You will later design your own experiment, so it is important that you know how to apply the skills for the section.

Note: all sections written in your lab notebook should be titled with the headings given below.

I Pre-laboratory assignment (in the lab notebook)
A. Laboratory objective
Briefly state the laboratory skills you will gain from this exercise.
B. Write the protocol
Write the whole protocol out in a step by step list of instructuions you can follow during class include all of the safety concerns for this lab. Also start thinking about how you will organize your data during the experiment.
C. Answer all pre-lab questions

II In-Lab assignment (in the lab notebook)
D) Alterations to the protocol
All the changes made to the protocol should be listed and a statement regarding why the change was made must be included. “Because the instructor told us to” is not a valid reason; the chemical basis for the change must be described.
E) Data Tables
In many experiments, it will be useful to organize your data in a table. In the early labs of this laboratory manual, sample data tables are included as a guide, however all data must be collected in the lab notebook.
F) Observations and Sources of Error
You should record in the laboratory notebook all observations made while performing the lab. Do not retype observations: they are to be the original copy of the observations made while in the lab. Examples of observations include color, color change, cloudiness and, consistency.
You should compile a list of mistakes or parts of the lab that did not work exactly as planned while you are doing the lab. Again, do not recopy it. It must be the original you made in the lab and must be clearly labeled with a heading. Following completion of the lab return to this section and analyze the effects the errors may have had on your results.

III Post-lab Assignment (in lab notebook)
G) Calculations
Some labs require numeric calculations. See individual lab handouts for details. Always use appropriate units and significant figures.
H) Results
Concisely state and present the final results of the laboratory.
I) Answers the Post-lab questions
Following each laboratory there are questions to help you understand the purpose of the laboratory exercise.
J) Discussion and Conclusions
Be sure to return to your sources of error and analyze how they may have affected your results in written form. Summarize the laboratory with a one paragraph conclusion.



Guided Experiments: Probably most of the labs you have done before are similar to the guided experiment. You will conduct a specific experiment utilizing techniques learned in the skill-building lab. The following sections should be included as outlined for the Skill Building Laboratories. In many of the guided experiments you will need to write parts of the protocol based on what you did in the Skill Building lab for that section.

Note: all sections written in your lab notebook should be titled with the headings given below.

I Pre-laboratory assignment (in the lab notebook)
A) Experimental objective
State the experimental objective. The objective is the experimental question you hope to be able to answer at the end of the experiment.
B) Write the protocol
Write the whole protocol out in a step by step list of instructuions you can follow during class include all of the safety concerns for this lab. Also start thinking about how you will organize your data during the experiment.
C) Answer all pre-lab questions




II In-Lab assignment (in the lab notebook)
D) Alterations to the protocol
All the changes made to the protocol should be listed and a statement regarding why the change was made must be included. “Because the instructor told us to” is not a valid reason; the chemical basis for the change must be described.
E) Data Tables
In many experiments, it will be useful to organize your data in a table. In the early labs of this laboratory manual, sample data tables are included as a guide, however all data must be collected in the lab notebook.
F) Observations and Sources of Error
You should record in the laboratory notebook all observations made while performing the lab. Do not retype observations: they are to be the original copy of the observations made while in the lab. Examples of observations include color, color change, cloudiness and, consistency.
You should compile a list of mistakes or parts of the lab that did not work exactly as planned while you are doing the lab. Again, do not recopy it. It must be the original you made in the lab and must be clearly labeled with a heading. Following completion of the lab and determination of your conclusion return to this section and analyze the effect the error may have had on your conclusions.

III Post-lab Assignment (in the lab notebook)
G) Calculations
Some labs require numeric calculations. Some labs require graphical analysis. Graphs should be included in the lab notebook. You may print them out and tape them into your notebook. See individual lab handouts for details. Always use appropriate units and significant figures.
H) Results
Concisely state and present the final results of the experiment. Results are manipulations of the data. Thus any numbers that were calculated from the data are results as well as graphical representations. You should write paragraph describing the results without drawing any conclusions from them.
I) Answers the Post-lab questions
Following each experiment there are questions to help you understand the purpose of the experiment.

J) Discussion and Conclusions
Be sure to return to your sources of error and analyze how they may have affected your results in written form. Summarize the experiment with a one paragraph conclusion.







Open Inquiry Experiment : This is the most challenging type of experiment you will perform. You will be given a biochemical topic related to the guided experiment(s) performed in that section of the lab manual. You will choose a problem related to that topic, perform any necessary research, and design an experiment that allows you to investigate it based on the knowledge you’ve gained from Skill-Building Laboratories and Guided Experiments. You must present your experimental design to the lab instructor prior to beginning the experiment.

Note: all sections written in your lab notebook should be titled with the headings given below.

I Pre-laboratory assignment (in the lab notebook)
A) Problem statement
This includes a few sentences describing the specific question(s) that you are trying to answer with your experiment. You should also include a brief (1-2 sentences) summary of the theoretical basis of your problem. For example: “The lipids should be separable from the carbohydrate because lipids are soluble in nonpolar solvents while sugars are water soluble.”
B) Proposed protocol
Please begin this section with a list of necessary equipment, supplies and chemicals. Followed by a stepwise protocol similar to the guided experiment protocol will be developed during the lab period following the guided experiment(s). You must outline in a step-by-step fashion exactly how you intend to carry out your protocol. Also included in this section the type of data you will collect (the variables you will measure, i.e. moles glucose and fructose produced in the reaction, optical rotation), and the safety considerations related to your experiment.

II In-Laboratory assignment (in the lab notebook)
C) Final Protocol and alterations
After receiving feedback from the instructor edit and note any additional changes made while performing the experiment.
D) Data Tables
All data collected during the experiment should be in your notebook in the form of tables.
E) Observations and sources of error
Observations should be included as outlined in Skill Building Experiments and Guided Experiments.
Sources of error should be included as outlined in Skill Building Experiments and Guided Experiments.
F) Calculations
Calculations on the data must be done to facilitate the analysis. Always use appropriate units and significant figures.

III Formal Report (Typed post- lab assignment)

G) Results
Concisely state and present the final results of the experiment, making use of tables where appropriate. Results are manipulations of the data. Thus any numbers that were calculated from the data are results as well as graphical representations. You should write paragraph describing the results without drawing any conclusions from them.

H) Discussion and Conclusions
In this section, briefly restate your problem and explain how the procedure you designed was supposed to help you address this problem. Analyze what the results say about the experiment, the procedure, and the problem. Be sure to return to your sources of error and analyze how they may have affected your results. State your conclusions.