Biology Lab
Report
Reference Guide
Step 1 - PROBLEM
• Poor example: What fertilizer is the
best?
• ***Clearly state the problem that you are
trying to solve. Be as specific as you can.
• Good Example:Which fertilizer,
Miracle Grow or VitaGro is best for
growing a particular species of roses?
• RESEARCH: Every good scientist spends
a great deal of time doing research so
that he/she can design experiments that
are meaningful and worthwhile. Research
is not limited to the written word, but
almost always involves communication
with other scientists interested in the
same topic. This collaboration is of
utmost importance in the research
community. You will need to use many
references to learn about the problem you
are tying to solve.
Possible questions you would need to
research about the “Good” problem stated
above:
• What does Miracle Grow contain?
• What does VitaGro contain?
• How fast do roses grow?
• What type of soil do roses like?
• Has this product ever been used on roses?
• What kind of nutrients do roses like?
• Do roses grow best is sun or shade?
• Do roses grow best is warm or cold climates?
• What kinds of roses are there?
• When do roses bloom?
Step 2 - HYPOTHESIS
• ****Now that you know what your
experiment is, what do you think will happen?
• Poor Example: I think the fertilizer will
help the plants. I think that the roses
will grow better with fertilizer
• Good Example: If I use Miracle Grow
instead of no fertilizer, then the flowers
with Miracle Grow will produce more
flowers compared to the one without
miracle grow.
Questions to Consider when
Designing an Experiment
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What organisms will I use?
How many organisms should I use?
What equipment will I need?
How will I set up my experiment?
What data will I measure?
What will be the manipulative variable?
What will be the responding variable?
Will I need a control set up?
How long will the experiment last?
How will I display my data? (data table, graph?)
DETERMINE the VARIABLES:
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1.
2.
3.
4.
5.
Variables (in general)– the parts of an
experiment that could vary or
CHANGE.
Independent Variable (the cause)
Dependent Variable (the effect)
Controlled Variables or Constants (stay the
same)
Controlled Set up vs. Experimental Set up
Sample size – determine amount needed for
an accurate conclusion
Step 3 – PROCEDURE (&
MATERIALS)
• Make sure that materials are very specific
• Poor Example : Roses, soil, water, fertilizer
• Good Example:
1. 150 red rose plants (same species) each 2 feet tall
2. 150 identical 5 gal buckets with 3 holes in the bottom
3. 10 bags of Home Depot brand potting soil (20 lbs.)
4. Miracle Grow fertilizer
5. VitaGrow fertilizer
6. Water
7. Graduated cylinder to measure water
8. Grow lights or green house
9. Yard stick
Procedure
• Your procedure should be
written in such a way that any
person using it could get
identical results.
Procedure
• Poor Example:
1.Plant roses, some with fertilizer,
some without
2.Water roses
3.Set plants under grow light
4.Count number of flowers
• GoodExample:
1. Fill 150 buckets with potting soil
to within one inch of the top.
2. Plant one plant in each bucket
so that all of its roots are covered
with potting soil.
3. Water each plant with 1 liter of tap
water.
4. Divide the plants into 3 equal
groups of 50 plants each, groups A, B
and C
Step 4 - DATA
• Decide what DATA to collect – Gathering data
accurately is one of the most important jobs of a
scientist. Often things that seem unimportant at
the time may later turn out to be quite significant.
• When designing an experiment, you must decide
what and how you are going to collect the data.
What will you measure. When will you measure it?
How will you display the data once it is collected?
Be sure to write it specifically in the procedures.
• *Typically the independent variable comes
first in the data table followed by the
dependent variable.
Types of Data
• A. OBSERVATIONAL DATA: Often when
experiments extend over a period of time,it
is important to describe in words anything
that seems significant. This may involve
routine, daily or weekly descriptions in a
journal format.
Ex: Week 1 – No roses have flowered yet,
not many leaveshave emerged yet
Week 2 – I noticed that the roses in groups
A and B are producing many more leaves
that Group C plants are. Still no flowers on
any plants.
• B. NUMERIC DATA: Numerical data
must be displayed in a data table. The
DATA TABLE should have a Title, and
be carefully labeled. You must use a
Straight Edge to draw your table
Good vs. Bad Data Tables
Experimental
Treatment
Group A - Miracle
Grow
Group B - Control
Number of Flowers
Produced
1500
3100
Graphing Data
• Each graph should have a title that describes what the
graph is about
• When graphing data, the independent variable always goes
on the X axis, and the dependent variable always goes on
the Y axis. .
• Each axis of the graph should be marked off in equal units
and properly labeled.
• In general, use a line graph when both axes are the set of
real numbers. Ex. Time, temperature, height, weight.
• In general, use a bar graph when one or both of the axes
are not the set of real numbers. Ex. Different kinds of
roach spray, people.
Step 5 - Conclusion
• -Restate your hypothesis.
• -State if your hypothesis was correct or
incorrect.
• -Answer your problem in a complete
sentence. (Always look back at your
purpose (problem) to be sure you answer
the right question).
• -PROVE your answer to your problem. Use
ACTUAL DATA from your experiment to
support your answer. This makes you
more credible.
• -Restate your findings as a concluding
thought.
Conclusion
SOURCES OF ERROR: Every time that you do an experiment, errors
may occur. It is more important that you identify errors that you
think could have affected the conclusion that you drew.
Poor Example: I didn’t always measure accurately. Some plants
may have gotten a little more water that the others. We had a
lot of cloudy days which meant less light.
Good Example: It was discovered that in the green
house, some of the plants were
shaded for part of the day while others got full sun. Those
that got
full sun produced more flowers.
Some of the plants became infested with tiny insects.
These plants did not produce as many flowers as the others.
Perhaps we should spray with an insecticide.