Lab: Interdependence of Organisms
Interdependence Of Organisms
Question Being Answered:
How can the presence of one species benefit another in the same ecosystem?
Hypothesis:
If plants grow in soil that contains worms the plants growth will be greater because worms are able to help decompose organic matter and help distribute it through the soil in a form plants are able to use.
Process Of Lab:
In this lab you will grow two different groups of plants. Group A is considered the experimental group which will grow in soil with worms, Group B is considered the control group which will grow in soil without worms. After the plants grow you have to measure the plant growth for both groups and compare them.
Independent & Dependent
Independent Variable: Presence Of Worms
Dependent Variable: Plant Growth
Safety Procedure
Be sure to follow the safety procedure which means to
Wear safety goggles and lab gown while doing the experiment
Keep lab behavior purposeful
Look over the soil contents and make sure to follow warnings provided on any equipment
Wash hands and lab equipment once done with experiment
Treat living organisms with respect and provide proper care
Report any accidents that happen in the lab to your teacher
Lab Procedure
Step 1: Gather Materials
Two trays that are 10 cm 4’ deep
Potting soil
Lima bean seeds which need to be soaked overnight
Location with sunlight or growth lights
Worms
Graduated cylinder
Water
Black marker
Ruler with metric markings
Step 2: Prepare Two Trays Of Lima Bean Plants
Label the trays Control Group and Experimental Group
Add approximately 6-7 cm of soil to each tray
Plant 6 lima bean seeds in each tray being 2 cm deep and label the plants 1-6
Step 3: Give The Plants Water And Light During Sprouting Time
Keep the environments for both groups identical
Water all the plants following the watering schedule that was recommended on the seed packaging
Use the graduated cylinder to ensure the same amount of water is being given to both groups
Make sure all plants get the same amount of light
Step 4: Measure The Heights Of The Plants At The End Of Week 1
Measure the height of all twelve plants to the nearest cm. If a plant dies mark an x on the data table for that plant and write it in your notes
Use a calculator to find the average heights of the living plants in each groups
Calculate the difference in those average heights by subtracting the average height of the plants in the control group. Use this difference as a basis for comparison
Record measurement observations in your notes and the health of the plants such as leaf colors and size, wilting, unusual growth, brown spots, and any other marks you see
Step 5: Add Six Worms To The Soil Of The Experimental Group Of Plants
Write descriptive notes about the condition of the worms in your notes
Step 6: Measure The Heights Of The Plants At The End Of The Week 3
Repeat step 4
Step 7: Measure The Heights Of The Plants At The End Of Week 5
Repeat step 4
Step 8: Check The Health Of The Worms At The End Of The Study
Are the worms still alive?
Do they all seem healthy?
Have they changed in any way? If so list the ways changed
Are there any new worms
Be sure to write descriptive notes about their conditions in your notes
Step 9: Dispose Of All Material According To The Directions From Your Teacher
Week 1 (Before Adding Worms)
Week 3
Week 5
Plant 1
10cm
22cm
49cm
Plant 2
9cm
23cm
47cm
Plant 3
8cm
20cm
49cm
Plant 4
9cm
22cm
50cm
Plant 5
10cm
22cm
47cm
Plant 6
8cm
23cm
52cm
Control Group Average
9cm
22cm
49cm
Plant 1
8cm
24cm
50cm
Plant 2
9cm
28cm
60cm
Plant 3
8cm
26cm
49cm
Plant 4
8cm
25cm
53cm
Plant 5
8cm
27cm
58cm
Plant 6
7cm
26cm
60cm
Experimental Group Average
8cm
26cm
55cm
Difference In Average Heights
-1cm
4cm
6cm
Table answers go from left to right in the order I put
