11.4 · Sorting Ohio Organisms by Role

From Ohio 5th Grade Science Power Workbook · Chapter 11 · Lesson 11.4.

Big idea: Any organism can be placed in a role by asking one question: how does it get its energy?

Learning goals: Sort unfamiliar organisms into the three roles

Justify a sorting decision with evidence

Explain what each of the three roles does for an ecosystem

One question, every time

You do not need to recognize an organism to sort it. You need to know how it gets its energy.

Makes its own food from sunlight — producer. Eats other living things — consumer. Breaks down dead material — decomposer.

Three roles, three jobs

Producers bring energy in. Consumers move it along. Decomposers break down what is left and return nutrients to the soil.

Without producers no new energy comes in. Without decomposers dead material piles up and nutrients stop returning to the soil. Consumers move the energy along.

Worked examples

Question: A student finds an organism in an Ohio stream. It is attached to a rock, it is green, and it does not move. Which role is it most likely to have, and what evidence supports that?

Steps: Ask the one question: how does it get its energy? Being green and in the light is a clue.

Green organisms in sunlit water usually make their own food.

So it is most likely a producer. To be sure, you would check whether it makes food or eats something.

Answer: Most likely a producer. It is green and sits in the light, which suggests it makes its own food rather than eating other organisms.

Common mistakes

You are sorting the role, not the animal

Ohio will sometimes describe an organism you have never heard of. That is on purpose.

You are not being asked to recognize it. You are being asked to read the clues about how it gets its energy and sort it.

Check your thinking: Underline the part of the question that says what the organism eats or how it lives. That is the clue you need.

Remember

Three roles, no gaps

Producers bring the energy in. Consumers pass it along. Decomposers send the nutrients back to the soil.

Practice tip

Remember: Unfamiliar organisms are on purpose.

Tip: A test question can name an organism you have never met. It is testing whether you can read the clue about how it feeds — not whether you recognize the name.

Written practice

An organism lives in an Ohio pond, is green, and is found only where sunlight reaches the water. Decide its most likely role and explain the evidence you used.

Sample response: It is most likely a producer. Two clues point that way: it is green, and it is only found where sunlight reaches. Producers need light because they use the sun's energy to make their own food, so an organism that can only live in the lit part of the pond is probably making food rather than eating it.

Scoring guide: 1 point: identifies it as most likely a producer.

1 point: uses the evidence — being green and needing sunlight suggests it makes its own food.

Ohio expects a role to be inferred from clues, with the reasoning stated.