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Unit 1: Interactions Within Ecosystems

Chapter 1: EcosystemsSection 1.3: Biotic Parts of the Environment

(Slide Show #3)

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REVIEW: Environment v.s. Ecosystem Environment

An organism’s surroundings. It is a place.

Ecosystem: The interactions that take place between the

biotic (living) and the abiotic (non-living) factors in the environment.

An ecosystem is not a place but rather a description of what is happening in a place.

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REVIEW: Environment v.s. Ecosystem You are now in your grade 7 classroom.

Describe the environment and the ecosystem.

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REVIEW: Environment v.s. Habitat What is an organism’s habitat?

A habitat is the environment in which an organism lives.

Can you describe your current habitat and environment?

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Biotic Parts of the Environment

In Section 1.3, you will learn four new key terms: Species Population Community Niche

What do you already know about each of these terms?

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Biotic Parts of the EnvironmentIntroduction (p.24) Why do you think it is important for

scientists to classify organisms into different groups?

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Biotic Parts of the EnvironmentIntroduction (p.24)

One way that scientists group organisms is to identify different species. A species is a group of

organisms that can reproduce among themselves to produce offspring of the same type that can also reproduce successfully. For example: Cats and

dogs are different species since they cannot mate with each other.

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Biotic Parts of the EnvironmentLevels of Organization (p.25) Let’s say that a scientist wanted to study

dogs. There are simply too many dogs in the world to consider them all at one time!

So, usually, scientists consider just the number (of dogs) in a particular ecosystem. A population is the entire group of

individuals of the same species that live together in one ecosystem at the same time.

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Biotic Parts of the EnvironmentLevels of Organization (p.25) What is the

population of dogs in this picture?

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Biotic Parts of the EnvironmentLevels of Organization (p.25)

Within any ecosystem there are many different populations of species.

Below, list at least 5 types of organisms that you would find during a fieldtrip of our schoolyard.

These organisms you listed, along with all the other organisms in our schoolyard, form a community.

Definition: All the interacting populations that live together in an ecosystem form a community.

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Biotic Parts of the EnvironmentLevels of Organization (p.25) How would you

describe this community of organisms?

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Biotic Parts of the EnvironmentNiche (p.25) Within a community, each species

uses the resources of the ecosystem in a slightly different way.

A niche describes the organism’s specific function (or job) in a particular community. It includes where it lives, how it feeds,

what it feeds on, and how it interacts with its environment.

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Biotic Parts of the EnvironmentNiche (p.25) The niche of a moose:

Lives in the boreal forests, bogs, and river and pond edges.

Feeds on plants Sometimes they can have a negative impact on

plant growth where populations are not controlled (by hunting)

Provides food for wolves In NL, no natural predators (although, sometimes

bears will eat calves or the very old).

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Biotic Parts of the EnvironmentReview

Choose an organism from the picture. Use it to describe the following:

Environment:

Ecosystem:

Habitat:

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Biotic Parts of the EnvironmentReview(continued…) Species:

Population:

Community:

Niche

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Section 1.3

Complete the following questions P.29, #1, 3, 5, 6, 9

Assignment Section 1.3 To show the meaning of the terms environment,

ecosystem, species, population and community, use them in a paragraph to describe an ecosystem of your choice. Include a diagram/picture. Note: This is part of Assignment #1C