Introduction to Ecology

Ecology- The Biosphere

Welcome to Ecology and the Biosphere, where we explore levels of

organizations in the living world and their interaction with their

environment. Come with us on this journey!

Levels of Organization

Individual Organism

An individual plant or animal is the first level

of organization in the ecosystem.

Population

A group of individuals of the same species

living together.

Community

The population of various species interacting

and living together in a given place.

Ecosystem

A community of different species interacting

with one another and the environment they

inhabit.

Biotic Vs. Abiotic Factors

Abiotic Factors

Non-living factors such as temperature, water,

light, and nutrient availability that impact

communities.

Biotic Factors

The living things in an ecosystem, their

interactions, and their influence on the

environment.

Multiple Choice

What is an example of an abiotic factor?

• Elephants

• Bacteria

• Soil

• Plants

Abiotic factors that influence living
organisms

Temperature

The average temperature, as

well as the daily and seasonal

variations, affects various

aspects of living organisms.

Water

The availability of water in an

ecosystem is critical for the

survival of all living organisms.

Soil

The quality of soil, including its

pH level, nutrients, and texture,

is a crucial abiotic factor for all

ecosystems.

Organisms: The Building Blocks of Life

Organisms are the basic building blocks of life and are found everywhere in the biosphere. They interact

with abiotic and biotic factors in their environment and play a vital role in the functioning of ecosystems.

Living Organisms in the Biosphere

1

Producers

Plants, algae, and phytoplankton, which

produce food from sunlight.

2

Consumers

Organisms that consume producers (herbivores/primary) or other consumers (carnivores/secondary & tertiary).

3

Decomposers

Organisms that break down dead tissue and

waste material to return nutrients to the

environment.

Match

Match the following organism with an example

• Grasses

• Primary Consumer

• Secondary Consumer

• Decomposer

Producer

Eats producers

Eats herbivores

Fungi

• Producer

• Eats producers

• Eats herbivores

• Fungi

The Three Trophic Levels

Producers

Producers, such as plants,

create their own food through

photosynthesis.

Consumers

Consumers, such as herbivores

and carnivores, eat other

organisms for energy.

Decomposers

Decomposers, such as fungi

and bacteria, break down dead

organisms and recycle their

nutrients back into the

ecosystem.

Food web and Trophic
Relationships

In an ecosystem, organisms rely on each other for food and energy.

Producers are the basis of all food webs, with different consumers

occupying different levels, and each level receiving only 10% of the energy

from the level below. Trophic relationships can be complex and involve

multiple species.

The 10% Rule

1
Only 10% of energy is
passed up in the trophic
level chain.

This means that a primary

carnivore only receives about

10% of the energy, not 100%,

of the herbivore biomass it

eats.

2
The rest of the energy is
either lost or used up as
a metabolic process.

This energy loss explains why

there are more producers

than primary carnivores in an

ecosystem.

The Biosphere: The Thin Layer
of Life on Earth

The biosphere is the thin layer of life on Earth where all living things exist.

This layer extends from the deepest parts of the ocean to the highest

mountaintops, and is home to a vast array of organisms, from the smallest

bacteria to the largest mammals.

Multiple Choice

If the 10% rule is accepted, how much energy will a snake (secondary consumer) gain from the 100% that is absorbed by the grasses after eating a rabbit (primary consumer)

• 1

• 10

• 100

• .1

Conclusion

By understanding the world around us, we can learn how to better manage

our environment and resources wisely. This knowledge will help us to

preserve the planet for all life forms.