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Students armed with Excel spreadsheets calculate the biotic potential of a tomato plant “taking over the world”
6, 7, 8, 9
Title – Tomatoes Take Over The Earth!
By – Erik Hanchett
Primary Subject – Science
Grade Level – 6-9
Determining the biotic potential of a tomato using an excel spreadsheet
Science: MSS4C3PO3, 4, 5
Students will determine the biotic potential of a tomato plant by counting the seeds of one tomato and then calculate the number of plants after three generations using an Excel spreadsheet.
- Write in your journal the following investigation question: How many descendants can one tomato plant leave behind in just three generations if every seed were to germinate, grow and produce fruit to its capacity?
- Record in your journal your guess (prediction) of the number of descendants that one tomato plant can leave behind in just three generations.
- Now graph out your prediction on the journal insert sheet (below).
- Now calculate using the journal insert sheet, the number of tomato plants that one tomato can produce in just three generations.
- Assume that tomato plants can self-pollinate and that each plant makes 100 fruits each season and then dies.
- Make a line graph of the population growth of your tomato over three generations on the journal insert sheet.
- What kind of growth pattern does the graph show?
- What will happen in just a few more generations?
- Why doesn’t this happen in real life?
- Use the terms exponential growth, limiting factors, and carrying capacity in a short paragraph to describe the results that you have graphed out:
An Excel sheet can be programmed so that students only have to enter the amount of seeds and Excel will automatically graph the result.
Journal Insert Sheet
|P (parent generation)||Tomatoes||None||a.|
|F1 (first generation)||Plants||1 plant per seed||c.|
|Tomatoes||100 tomatoes per plant||d.|
|Seeds||d. x b.||e.|
|F2 (second generation)||Plants||1 plant per seed||f.|
|Tomatoes||100 tomatoes per plant||g.|
|Seeds||g. x b.||h.|
|F3 (third generation)||Plants||1 plant per seed||i.|
Spreadsheet checklist and answers to questions
E-Mail Erik Hanchett !