EC: Introduction to Ecology and Biomes Lesson
It's Classified!
You may have remembered from the beginning of biology that life is classified - cell, tissue, organ, organ system, and organism.
Scientists also classify how organisms interact with themselves, as well as with the world around them.
See the diagram below for more information.
Ecological Levels
Ecology focuses on the organism and how it interacts with each of these levels.
Level |
Definition |
Example |
|---|---|---|
| Biosphere | The portion of the Earth and atmosphere where life exists | The air, water, and terrestrial areas where life can exist; biome plus atmosphere |
| Ecosystem | The living things in an area, along with their environment | The seashore including all the animals, plants, algae as well as the wind, minerals/rocks, water and weather |
| Community | All of the populations that live in a defined area | All the animals, plants, fungi and bacteria that live together in a forest |
| Population | A group of individuals in the same species within a defined area | Squirrels in your neighborhood or algae growing in a test tube |
| Organism/Species | A living thing, unicellular or multicellular that lives in the same location and can interbreed with others of its kind | Blue whale, mushroom, pine tree |
We will begin our study of Ecology by focusing on the biosphere.
Biomes
As you can see from the chart above, the biosphere is made up of the biome and atmosphere.
What exactly is a biome?
A biome is a large area of land with similar plants, animals, and climate. A biome is composed of similar ecosystems.
Two major groups of biomes exist:
- Aquatic biomes- based on water, such as oceans or freshwater lakes
- Terrestrial biomes- based on lands, such as tropical rainforests, or deserts
The abiotic factors in a biome (temperature and precipitation) will define what sort of plant life can exist in an area. This in turn, determines the habitats for other living things.
Aquatic Biomes
- Marine biomes- bodies of seawater (more than 1% salt) such as oceans, coral reefs and estuaries (where ocean meets streams/rivers)
- Freshwater biomes- bodies of water that contain less than 1% salt, such as ponds, lakes, streams, rivers and wetlands (standing water)
Terrestrial Biomes
Do you know which biome you live in?
What do Ecologists look at when studying the biosphere?
Abiotic and Biotic Factors
The biosphere is the portion of the earth that can support life, from the soil to the oceans, and even the atmosphere where birds fly.
- Abiotic factors are the nonliving physical conditions or resources that affect living things in the biosphere. These include soil, water, air (oxygen, carbon dioxide), temperature, and sunlight.
- Biotic factors are the living things in the biosphere. These include bacteria, other microorganisms, fungi, algae, plants, and animals.
Look at the picture below. What are the abiotic and biotic factors you see?
If you said any of the following:
- Biotic – bird, cat, orangutan, plant, tree
- Abiotic – stream, sunbeams, soil, and air
Then, you have a good understanding of biotic and abiotic factors!
Challenge and Before You Go
Practice Time! Use the knowledge you learned from the lesson to complete the practice activities below.
Answer Key Links to an external site.
Before You Go - You Need To Know
The following key points are from the explore section of the lesson. You must know the following information before moving to the next lesson. This is just a summary of the key points.
- How do ecologists classify organisms and the environment (from more specific to most general)?
- The organism, population, community, ecosystem, and the biosphere
- What is the difference between abiotic and biotic factors?
- Abiotic means “nonliving”, while biotic means “living”. Examples of abiotic factors include soil, water, and temperature. Biotic examples include bacteria, plants, and animals
- What is a biome and how are they divided?
- A biome is an area of land that has similar plants, animals, and climate. Biomes are divided into two main groups: aquatic and terrestrial.
IMAGES CREATED BY GAVS (FREEPIK)