Topic: Producers, Consumers, and Decomposers

Author: Leokadia Stalewicz

Target group

8th‑grade students of elementary school

Core curriculum

General requirements

I. Knowledge of biological diversity and basic biological phenomena and processes. Student:

3. presents and explains the relationship between the organism and the environment.

Specific requirements

VII. Ecology and environmental protection. Student:

5. presents the trophic structure of the ecosystem, distinguishes producers, consumers and decomposers and presents their role in the circulation of matter and energy flow through the ecosystem.

General aim of education

You will learn the relationships between producers, consumers and the decomposers. in the ecosystem

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• indicate food dependence in the ecosystem;

• identify organisms as producers, consumers, destructors.

Methods/techniques

• expository

  • talk.

• activating

  • discussion.

• exposing

  • exposition.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers.

Lesson plan overview

Before classes

• Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

Introduction

• The teacher explains the aim of the lesson and together with students determines the success criteria to be achieved.

• Then he writes the subject of the lesson on the blackboard or interactive whiteboard. Students write it in notebooks.

Realization

• The teacher divides the class into groups and each of them allocates one of the following topics: producers and their role in the ecosystem; consumers and their role in the ecosystem; decomposers and their role in the ecosystem.

• The teacher indicates the persons who will report consecutively assigned topics. After completing the statements of colleagues, students from other groups can ask questions and ask for additional explanations. All students who have been assigned a given topic provide answers.

• The teacher presents the infographic „Relations between producers, consumers and decomposers”, and summarizes the students' statements. He also explains that all trophic levels are equally important and necessary for the proper circulation of matter in the ecosystem.

• The teacher presents the „Relations between producers, consumers and destruents” infographic, and summarizes the students' statements. He also explains that all trophic levels are equally important and necessary for the proper circulation of matter in the ecosystem.

• Students perform exercises and commands. The teacher checks and supplements the answers, providing students with the necessary information. Provides feedback..

Summary

• At the end of the lesson the teacher asks: If there was going to be a test on the material we have covered today, what questions do you think would you have to answer? If the students do not manage to name all the most important questions, the teacher may complement their suggestions.

Homework

• Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

• Write a short note about the topics covered in the lesson.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Producers, Consumers, and Decomposers

The basis for the functioning of most ecosystems is the presence of autotrophic organisms, the so‑called Producers. During the process of photosynthesis, producers produce organic matter (biomass). The amount of organic plant matter (produced per year per unit of ecosystem area) is used to assess the rate at which producers convert solar energy in the process of photosynthesis. It is different for different ecosystems (see figure below). The main factors conducive to the rapid growth of plant mass are respectively high temperature and humidity, long vegetation period and soil fertility.

The production of organic matter takes place both on land and in the aquatic environment. Both in fresh and salt water, there are many plants and autotrophic bacteria and protists. Water covers about 2/3 of the Earth's surface, which is why biomass production in the oceans is a significant part of the total biomass production on Earth.

The higher the mass of organic matter produced by plants per year, the more herbivorous animals can sustain themselves in a given ecosystem. They eat grass, leaves, fruits, seeds and even roots, wood and bark. The obtained nutrients are used by herbivores as an energy source and built into their own bodies, thanks to which they can grow and reproduce. Herbivores are food for carnivores. These, in turn, may fall prey to other predators, often larger than themselves.

Both herbivores and carnivores use other organisms (plant or animal) as food. In the ecosystem, every heterotrophic organism is called the consumer. Consumers can be sorted by certain categories. And so herbivores are called first‑order consumers. Second‑order consumers are the carnivores eating them, and the third and the next‑order consumers are carnivores feeding on other carnivores. Omnivores, depending on what they consume at the moment, belong to consumers I, II, III or any of the higher orders.

Producers are the largest biomass in ecosystems. Biomass of consumers on consecutive trophic levels makes up about 10% of the previous level.

Heterotrophic organisms that feed on the dead organic matter are called saprobionts. Some of them perform the function of decomposers in ecosystems. They are able to decompose the remains of organisms into mineral compounds, which then become air (carbon dioxide and water) and soil (mineral salts) and can be taken up by plants. Thanks to this process dead organic matter are not in arrears in ecosystems, but decomposed into simple substances is re‑incorporated into organisms - first plants and later animals. Decomposers include bacteria and fungi. Their presence in ecosystems is essential. Without their activity, the circulation of matter (circulation of elements) in nature would be impossible.

• All organisms in the ecosystem are connected by complex food dependencies – they form food (trophic) chains and trophic networks.

• The ecosystem is distinguished by trophic levels: producers, consumers of the first, second and subsequent orders, and decomposers.

• The decomposers break down dead organic matter into inorganic matter.