Bacteriology 102: Flow Charts and Tables
I. Preparation of "Flow Charts" – relevant to poster presentations and lab preparation in general.
A. Example of a General Flow Chart.
As a good table can collect and organize the observations and results obtained for various known and unknown organisms studied in the lab, a good flow chart can present a concise overview of the relationships of the various activities that were done in the experiment. Part of your lab preparation (i.e., coming to lab prepared!) should be checking the schedule to see what is coming up and looking closely at the various activities to be performed. Nothing beats some good flow charts to help you plan your work efficiently, especially when there are several different experiments happening in the same lab period.
When making a flow chart, one must avoid connecting all of the activities performed in linear fashion. Rather than copying the directions in the manual verbatim and then connecting sentences or paragraphs with arrows, you can improve upon those directions – making sure you are retaining important inoculation and incubation directions and also refraining from excess wordiness. If one makes wet mounts of an enrichment and then streaks plates from the enrichment, there should not be an arrow drawn between the two activities as if to show the plates were streaked from wet mounts!
A flow chart can be made as general or specific as one sees fit. The example illustrated on the right gives a general overview of the procedure for Experiment 11.1 in Bacteriology 102 wherein purple non-sulfur photosynthetic bacteria are isolated by enrichment and plating. This is a continuous flow chart, not divided into the several "periods" as indicated in the lab manual for this experiment. This kind of general flow chart is appropriate for posters, making for easy connection by the poster-viewer between procedures and results at various stages of the experiment, and all essential parts of the procedure are represented. Note the orientation toward materials being connected with the arrows. The methods are indicated as concisely as possible; the author of this flow chart does not label specifically the inoculations if they appear understood. Set off laterally are indications where observations and/or tests are made (the results being summarized in the "Results" section of the poster).
The following general outline for Experiment 11.2 (isolation of Bacillus) may be considered a flow chart and can be made more specific by indicating incubation conditions (time and temperature) and where observations were made (summarized elsewhere in appropriate tables). The use of indentations can show relationships between the various things set up in the procedure.
II. Preparation of Tables – relevant to our lab reports, poster presentations and the tabulation of results in general.
When it comes to indicating results in a report or poster, the observations of enrichments (which are always mixed cultures) should always be kept separate from observations and reactions of the individual isolates. For example, in Exp. 11.1 on the purple non-sulfur photosynthetic bacteria, one could describe one's observations of the enrichment as follows: "Red, cloudy growth observed throughout the bottle. Wet mounts showed motile and non-motile rods and oval cells, and motile spirilla."
Then, once isolates are obtained (that is, once individual colonies are seen and considered for further study), the recording of information concerning them (and their subcultures) should be put in a table – an example of which is shown below. Note that macroscopic and microscopic observations on the colonies are included as well as the results of further tests made on cultures inoculated from the same colonies. Tentative genus identifications can be included. One could add a column analyzing the Succinate Agar tube results in which case Isolate A would be a "strict phototroph" and Isolate B would be a "facultative phototroph." (As another example of a table, one suitable for our Streptomyces isolation experiment is shown on page 52 in the manual.)
|growth in Succinate Agar tubes||tentative|
|in light||no light|
|A||tiny, red, hard||oval cells connected by filaments||no aerobic growth; anaerobic growth with red pigmentation||no growth||Rhodomicrobium|
|B||large, orange, mucoid||curved, knobby rods||white aerobic growth; red anaerobic growth||white aerobic growth; no anaerobic growth||Rhodopseudomonas|
Note the new guidelines for reports and posters which replace the equivalent material in the lab manual (Appendix 11A) and what was here on the web.
Here we reiterate a major point about our experiments which is stated on the general enrichment/isolation page: Considering all of the examples (real and hypothetical) that we could give and all of the similar experiments one could read about in journals, realize that each situation is unique. Never expect to replicate anyone else's results or any supposed "typical" result! We may isolate representatives of several genera from one sample and several species of one genus from another. Habitats and samples will vary considerably from each other, and will vary themselves over time. We may spot a "trend" and we may isolate something entirely new; these are things that are fun to follow up on.