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Science_Lab_Yellow / Lesson 1: Ecosystem

What will we be learning today?

  • In this lesson, we are going to learn all about the ecosystem.

What Is an Ecosystem?

  • What or whom do you interact with every day? Living things and nonliving things interact in an ecosystem. An ecosystem is all the living and nonliving things in an area. Ecology is the study of how all these things interact in order to survive.

  • An ecosystem may be very small, such as a backyard or pond. Some ecosystems, like the prairie ecosystem of North America, the deserts of Africa, and the rain forests of Brazil, cover large areas of a country or continent. Freshwater ecosystems cover less space than saltwater ecosystems. Saltwater ecosystems can cover entire oceans. It doesn't matter where they are or what they look like, all ecosystems have the same parts.

  • Abiotic Factors


    • The nonliving parts of an ecosystem are the abiotic (ay ·bigh ·AHT ·ik) factors. All living things need certain nonliving things in order to survive. Abiotic factors include water, minerals, sunlight, air, climate, and soil.


  • All organisms, or living things, need water. Their bodies are 50 to 95 percent water. The processes that keep living things alive-like photosynthesis and respiration-can only take place in the presence of water. Living things also need minerals, such as calcium, iron, phosphorus, and nitrogen. Some living things, like plants and algae, need sunlight to make food. Animals need oxygen to produce energy for their bodies. Plants and algae need carbon dioxide. The environment must also have the right temperature for organisms to survive.

  • Biotic Factors

    • The right abiotic factors help make it possible for organisms in an ecosystem to survive. The living parts are animals, plants, fungi, protists, and bacteria. Mushrooms and molds are examples of fungi. Protists include one-celled organisms.

  • These organisms-animals, plants, fungi, protists, and bacteria-make up the biotic (bigh ·AHT ·ik) factors, or living parts, of an ecosystem.


  • Plants and algae are called producers. They produce oxygen and food that animals need. Animals are consumers. Animals consume, or eat, plants or animals. Animals also give off carbon dioxide that plants need to make food.

    • What do the fungi and bacteria contribute? They are a very important part of any ecosystem. Fungi and bacteria are decomposers. They decompose, or break down, dead plants and animals into useful things like minerals that enrich soil. Plants need these in order to grow.

    • Each of these kinds of organisms helps the others survive.

    Biotic factors in an ecosystem include plants, animals, fungi, protists, and bacteria.

    Let's Review What We Learned Today!

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