STEM Brine Shrimp Lab- Day 2

Today you are going to design an experiment to test a variable of your choice relating to brine shrimp.

Suggestions for variables  (or come up with your own area) that affect the hatching rate of brine shrimp eggs:
     - Temperature
     - Salinity (salt content) of the water
     - Size of container
     - Type of container
     - Ratio of eggs to water

If you are working with salinity, a heaping spoonful of salt in a liter of spring water will give you a salt concentration of 25 parts per thousand.   You can vary the amount of salt to change the concentration.

In your composition notebook you should already have a this lab titled and a 10 sentence section titled 'Background.'

Working with your group members you job today is to come up with your:

Problem- (Stated as a question)

Hypothesis- (What you are predicting what will happen in your experiment)

Materials- (A list of the materials you will need for your experiment)

Procedure- (A DETAILED NUMBERED list of the steps of your experiment)

On the index card Mrs. Keller provides, write a list of materials your group will need for Thursday.  Be complete and specific as possible. Turn this in to Mrs. Keller. 

STEM Brine Shrimp Lab- Introduction and Research

After Keystone testing is over, we will do our final project of the year, Brine Shrimp.

You may have seen brine shrimp marketed as "Sea Monkeys" or even had some when you were a kid!

Today you will need to do some background research with brine shrimp so that you have a depth of understanding necessary to do your lab work.

Title this section of your composition notebook, "Brine Shrimp Lab."

Underneath the this, title the first section, "Background."   Then visit the following links to learn more about brine shrimp.  Write a 10-sentence paragraph summarizing what you learned about brine shrimp.

Brine Shrimp from Learn Genetics

Brine Shrimp from the Great Salt Lake Ecosystem Project

Brine Shrimp in the Great Salt Lake of Utah

Brine Shrimp from Wikipedia


After you are done with your research, think about who you would like to work with in your group (groups of 3 to 4 are good), and in what area your might like to conduct your research.  You might research one of the following areas (or come up with your own area) that affect the hatching rate of brine shrimp eggs:
     - Temperature
     - Salinity (salt content) of the water
     - Size of container
     - Type of container
     - Ratio of eggs to water

After the Keystones you will come together in your group, formulate a hypothesis, and design and complete an experiment to test your hypothesis.

 

Popcorn Energy Flow STEM Lab

Introduction:

In this lab you will create a model of energy flow through FOUR TROPHIC LEVELS of an ecological system.  You will use popcorn and various containers to represent energy flow through each trophic level. (There are  is NOT just one correct way model this.)  You will need paper and a calculator. You will practice using the metric system and calculating percentages.  You will then design a Google Slides presentation  and conclude the lab by teaching your class about energy flow in ecosystems.

Materials:

·                         One bag of popcorn per group.  All of this popcorn must be included on the bottom of your                    energy pyramid (1st Trophic Level)

·                        A variety of containers to represent trophic levels 

                One large plastic bag

               A piece of manilla tagboard to be used as a scoop/funnel

·                         Electronic balances and triple beam balances to calculate the amount of energy proceeding from one level to the next. (Remember, you need to mass only the energy and not the container you have on the balance, so subtract the mass of the container.)

·                          Broom and dustpan

·                          Chlorox Wipes (the waste energy gets all over the lab tables and leaves a greasy residue)

Directions:

1. Work in groups of about 4.

2. Read the section on page 77 of your textbook titled, "Pyramids of Energy."

3. Obtain 1 bag of popcorn from the Energy Supply area. Be sure to note special information on the bag (i.e. mass or volume).  This information may prove useful when you need to perform calculations. DO NOT THROW THE BAG AWAY!

4. Select containers from the materials at the Trophic Level Building Supply Store. You will use these to build a model of energy flow. 

5. Work to create a model of energy flow using your materials. You will write up your procedure such that another scientist could replicate your model. This means each step needs to be justified and explained thoroughly.

6. Special hint---remember only 10% of energy that enters a system makes it to the next trophic level. You need to be able to quantify the amount of energy that leaves a system as waste and the amount that makes it to the next trophic level. This is where the balance and calculator come in.  Include these calculations in your presentation.

7. When you are satisfied with your model, you will show create a 6 to 7 slide Google Slides presentation showing your procedure and results. Take photos with your phone to use in your presentation.   These photos should document your procedure.  Share your presentation with a few group members and nkeller@penncrest.org.

8. Each group will give their presentation on Friday.  You will explain your model to the class as you click through the presentation. 

9. While you are giving your presentation, include the following information:

               In the model, energy is represented by ____ and trophic levels are represented by ____.

               Describe the steps you used to represent energy flow.

              Identify the  types of organisms found at each level of the Pyramid of Energy

              Explain how you calculated the amount of energy lost between trophic levels.  Show your calculations of the amount of energy you began with, as well as the amount lost at each level and passed on at each level. 

              Explain where the missing energy goes.

              Explain why there are very rarely more than 4 levels in an Energy Pyramid.

              Explain why you think you had to do this lab. 

10. Eat your popcorn or throw it away! 

Adapted from a lab by Dr. A Scott, Athens Academy, Athens, GA