Certain general rules are commonly followed in scientific writing:
Readers interpret prose more easily when it flows smoothly, from background to rationale to conclusion. Don’t force the reader to figure out your logic – clearly state the rational. In addition, it is much easier on the reader if you explicitly state the logic behind any transitions from one idea to another.
Use standard abbreviations (hr, min, sec, etc) instead of writing complete words. Some common abbreviations that do not require definition are shown on the attached table. Define all other abbreviations the first time they are used, then subsequently use the abbreviation [e.g. Ampicillin resistant (AmpR)].
As a general rule, do not use an abbreviation unless a term is used at least three times in the manuscript. With two exceptions (the degree symbol and percent symbol), a space should be left between numbers and the accompanying unit. In general, abbreviations should not be written in the plural form (e.g. 1 ml or 5 ml, not mls).
Past, present, and future tense
Results described in your paper should be described in past tense (you’ve done these experiments, but your results are not yet accepted “facts”). Results from published papers should be described in the present tense (based upon the assumption that published results are “facts”). Only experiments that you plan to do in the future should be described in the future tense.
Third vs first person
It is OK to use first person in scientific writing, but it should be used sparingly – reserve the use of first person for things that you want to emphasize that “you” uniquely did (i.e. not things that many others have done as well). Most text should be written in the third person to avoid sounding like an autobiographical account penned by a narcissistic author. However, it is better to say “It is possible to ..” than to say “One could …”. Writing that uses the impersonal pronoun “one” often seems noncommittal and dry.
In addition, inanimate objects (like genes, proteins, etc) should be described in third person, not with anthropomorphic or possessive terms (e.g., instead of saying “its att site”, say “the chromosomal att site”).
Avoid using phrases that do not contribute to understanding. For example, the following phrases could be shortened (or completely deleted) without altering the meaning of a sentence: “the fact that …” (delete); “In order to …” (shorten to simply “To …”). Likewise, the title of a table of results does not benefit from the preface “Results of …”. In short, don’t use more words than you need to make your point.
If several expressions modify the same word, they should be arranged so that it is explicit which word they modify. It is common to use a pronoun such as “it” or “they” to refer to a concept from the previous sentence. This is OK as long as there is only one concept that “it” or “they” means.
However, if there are more than one concepts it is easy for the reader to get confused about what the pronoun is meant to specify (even if you know which one you mean). It is better to error on the side of redundancy by repeating the concept in subsequent sentences, than to take the chance of confusing the reader. Don’t make the reader guess what you mean.
Avoid double parentheses. For example, “Three gene products catalyze reactions in the pathway for proline biosynthesis (Figure 1) (3)” could be reworded to say “Figure 1 shows the three reactions of the pathway for proline biosynthesis (3).”