Writing for Biology ClassPart 2: How to Write Each Section of a Lab Report

Materials taken from Knisely, Karin. Writing in Biology. 2009 Sinaur/Freeman and edited by

Angela Bush, SRVHS

The Pre-Lab• All laboratory assignments begin with a pre-

lab• Pre-labs are essential for being prepared for

the lab activity. They ensure:1) Student safety during the lab2) Successful completion of the lab in the limited time

class allows3) Increased student understanding of the lab4) An increased chance of desired results from the lab

• This portion of the lab includes the purpose, hypothesis and procedure

– Done in lab journal (or typed if preferred)– You must read and be familiar with the lab prior to

writing a purpose or hypothesis!– ULTIMATLEY MUST BE TYPED FOR FORMAL LAB

REPORTS

Procedure• Because you need to read the lab before writing

the purpose and hypothesis, the procedure is a good place to start!– Though in your report, the purpose and hypothesis still

come first!• Summarize all the steps of the lab.

– Be detailed, but don’t exactly copy the lab manual or simply change a few words. Plagiarizing your teacher is still plagiarism!

– Someone should be able to repeat the lab based on you notes in this section. 

• Avoid listing materials, containers & elaborate procedures.

• Its ok to summarize as long as you still have enough info to perform the lab!

– Include any pictures, measurements, tables, etc. made/used during the lab in this section

– Please number your steps (no bullet points, no paragraphs)

Procedure Samples• Example:

– Original: Label six clean beakers with the following concentrations of sucrose and create and place those solutions in the appropriate beaker: 0, 7%, 14%, 21%, 28%, and 35%.

– Revision: Label beakers: 0%, 7%, 14%, 21%, 28%, and 35%, and place the appropriate sucrose solutions in each beaker

• Example 2: – Original: Place a few yeast under a

microscope and draw what they look like. – Revision: Observe and draw yeast under a

microscope

Procedure Samples• Example:

– Original: Label six clean beakers with the following concentrations of sucrose and create and place those solutions in the appropriate beaker: 0, 7%, 14%, 21%, 28%, and 35%.

– Revision: Label beakers: 0%, 7%, 14%, 21%, 28%, and 35%, and place the appropriate sucrose solutions in each beaker

• Example 2: – Original: Place a few yeast under a microscope

and draw what they look like. – Revision: Observe and draw yeast under a

microscope• Unless you have come up with the idea and procedure

for this lab, reference the original lab or other references used for the summarized steps! Use the number of the reference according to your reference page, in parentheses, after the sentence(s) containing the information (or after entire section if it all came from one reference).

Purpose

• Purpose: What is the point of the lab, what are you trying to learn, why it is interesting, etc. – Approx. 1-2 sentences to 1 paragraph– A statement not a question!

• Example:– Purpose: The purpose of this lab is to

observe osmosis using carrots and varying sucrose solutions.

Hypothesis• Hypothesis: If---, then----, (because----)

– If (IV), then (DV), because (prediction, guess, explanation of known causes)

– NOTE: Again, this will be easier to do after you have read the lab! 

– Find key words or concepts

Hypothesis Example• You are working with sand and yeast. You will

observe both for signs of life using a microscope and a sugar-water mixture.

• IV? – Using a microscope and a sugar-water mixture

• DV?– Signs of life

• Hypothesis: – If a microscope and a sugar-water mixture are used, then yeast and/or sand will show signs of life

• Do you have any prior knowledge that can help make this more specific?– If a microscope and a sugar-water mixture are used,

then yeast will show signs of life and sand will not because yeast is a fungus and sand is made of rock particles.

Prior to the Lab Experiment• Know what to expect from the experiment

– Know the hypothesis and what the outcome will be if the hypothesis is write!

• Recognize other (standard) variables– Know what other variables may effect the lab so

you can do your best to control them• What should remain constant? Make sure they do!

• Identify a control group or groups– Groups using standard variables

Writing Titles for Lab Reports

• The Effect of the IV on the DV• Example:

– The hypothesis was:• Hypothesis: If a microscope and a sugar-water

mixture are used, then yeast will show signs of life and sand will not because yeast is a fungus and sand is made of rock particles.

– The Effect of using microscopes and sugar-water on determining whether sand and yeast are living or not living

During the Lab Experiment• Collection of observations and data

– Throughout the lab use your senses to make observations! What could one, hear, smell (if appropriate), taste (if appropriate), and touch (if appropriate) during this lab.

• Note these observations, you never know what will be important when you start to draw conclusions!

• Qualitative- make notes in your journal, it will help you with your lab report!

• Quantitative- use a data table to collect numerical data, with units of measurement

• Make drawings with dimensions and magnification, where appropriate.

• Think about questions, possible errors, and other anecdotal notes as you go, it will help with your lab report! – Decide if the data is trustworthy or erroneous, if you

have time you may need to repeat a portion of the experiment

Observations • Answer all observation questions, include any graphs

necessary. • Number answers (rather than putting them in

paragraph form)• For a formal lab report, you should have at least 3-4

sentences of your own observations (in addition to your answers to the observation questions).– Use your senses and state only facts, no inferences or

conclusions

• Use proper grammar and “good writing techniques” (see Writing for Biology Class Part 3: Grammar) 

• If references are used, be sure to include the number of the reference according to your reference page, in parentheses, after the sentence(s) containing the information.

Conclusions• Answer all conclusion questions• Number answers (rather than putting them in paragraph

form)• Write your “power conclusion”, your conclusion is your

summary of the experiment, the data you collected, experimental error, and future implications for experimentation. Use the power conclusion writing help to make sure you have included all aspects of a good conclusion. – You may be given some additional questions or prompts in the lab to

make sure you analyze the most important aspects of the lab

• If references are used, be sure to include the number of the reference according to your reference page, in parentheses, after the sentence(s) containing the information.

• Use proper grammar and “good writing techniques” (see Writing for Biology Class Part 3: Grammar) 

References• Include a references list for any references used,

including your text book, to find information or definitions to help answer questions or make statements in the observation and conclusion portions of the lab

• Use APA format– For help creating APA references go to the Citation

Machine Website, on the left hand side of the screen select MLA, then the appropriate reference type.

• NOTE: You need a reference section AND in text citations. Proper APA in-text, or parenthetical, citations use the author’s last name and the year of the publication, for example (Tomada, 2015). It is ok to just put the number marking the reference in your reference section in parantheses. Exp, if the lab was your first reference, labeled 1)… in your reference section you may use (1) in your lab report next to any appropriate information