Name: ____________________________________________
Period: _____
Scientific Method Lab: Sea Monkeys
Introduction:
We will be growing sea monkey eggs in various concentrations of salt water to see which concentration
hatches the most eggs. The concentrations we will be using are 0% (fresh water), 2% salt, and 4% salt.
Problem:
What is the problem in this experiment? Write this as a question!
Research:
In “the real world,” scientists do not just simply experiment when the thought crosses their mind; they
research the topic first. Before you begin this lab, research the questions below to learn a little about sea
monkeys.
1.
2.
3.
4.
5.
6.
What other name do people call sea monkeys?
What is the scientific name of the sea monkeys (genus, species)
How big are sea monkeys?
What will a sea monkey look like when it hatches? Describe or draw one.
Name 2 common types of animals that sea monkeys related to?
In what environment(s) are sea monkeys normally found in nature? (Where do they normally
live?- Give details)
7. What do sea monkeys eat in nature?
8. How do sea monkeys reproduce? (there are two ways, explain both)
9. What is the purpose of a “cyst”?
Hypothesis:
Write your hypothesis …remember that this is the answer to your question (problem) from question 1.

Hypothesis: If….then…because…
Setting up the experiment:
1. What is the independent variable?
2. What is the dependent variable?
3. List any important constants (name 5 important ones).
Materials:
If you do not know what any of these materials are please look them up on Google image search.
3 Petri dishes
Labeling Tape
Marker
Graduated cylinder
Salt water solutions (premade for you)
Fresh water
Sea monkey eggs
Stereoscope (dissecting microscope)
Procedure:
Day 1 Procedure:
1. Label 3 petri dishes with the various salt water concentrations (0% salt, 2% salt, 4% salt).
2. Fill petri dish with 10mL of appropriate salt water concentrations.
3. Add a small amount of sea monkey eggs to each petri dish.
4. To determine the amount brine shrimp eggs in each petri dish, we will use a random sampling
technique:
a. Trace around the base of the petri dish on a sheet of paper.
b. Remove the petri dish and draw four quadrants in your circle.
c. Place the petri dish back on the circle and evenly spread out all the eggs.
d. Count the number of brine shrimp in one quadrant and multiply that number by four.
5. Record the total number of brine shrimp eggs in the data table below.
6. Place petri dishes near heat lamps. Allow 48 hours to hatch.
Day 2 Procedure:
7. Obtain your petri dishes and a stereoscope. Be careful not to spill!
8. Determine the amount of eggs in each petri dish using the random sampling technique from Day 1.
9. Dispose of sea monkeys down the drain. Clean all dishes thoroughly and put your supplies away.
Results & Data:
Data Table: Fill in ALL parts of the table.
Group Data
Salt
Concentration
0%
2%
4%
Number of eggs
in your dish
Number of
hatched sea monkeys
Class Data
Percentage of
hatched sea monkeys
Average percentage
of hatched sea
monkeys
Graph: Create a line graph to illustrate your group’s data and the class average data.
Helpful Hints:
*Dependent Variable goes along the x – axis. (Make sure intervals and spacing are consistent)
*Independent Variable goes along the y – axis. (Make sure intervals and spacing are consistent)
*Write a title
*Make a key/legend color coding the two lines
*One line should be your group’s data
*Second line should be the class’ data
Analysis Questions:
1. Which salt concentration supported the highest percentage of sea monkey eggs to hatch?
2. Why did you use a random sampling technique to count the sea monkey eggs?
3. What other experiment might you be able to test on the rate of sea monkey eggs hatching?
Conclusion:
Write a conclusion that describes and explains the results of your lab. You may use the following as a
guideline.
1. State your hypothesis and whether it was supported or rejected.
2. Explain why your hypothesis is supported or refuted (refer to specific data & describe your logic).
3. Discuss how your experiment relates to biology (sea monkey life).
4. State your possible sources of error and how these errors may have impacted your results.