Chapter 2Ecology

Ecology the study of interactions

that take place between organisms and their environment

The biosphere is the portion of Earth that supports living things.

It extends from high in the atmosphere to the bottom of the oceans.

The BiosphereThe Biosphere

Biotic Factors

The Living parts of the environment.

(giraffe, trees, grass…)

Abiotic Factors

The Nonliving parts of the environment.

(temp., humidity, rocks, water…)

Levels of Organization

Organism – Species – Population

– Community – Ecosystems

Species

Population

Community

Niche The role an organism plays in its

environment. Rule: No two organisms can occupy the same niche at the same time for very long.

Ecosystem

Made up of interacting populations in

a biological community and the

community’s abiotic factors.

There are two major kinds of ecosystems—terrestrial ecosystems and aquatic ecosystems.

Organisms in EcosystemsOrganisms in Ecosystems A habitat

is the place where an organism lives out its life.

Symbiosis Living Together

3 Types

Mutualism Both species Benefit

from the relationship.

Parasitism One species benefits

the other is harmed

Commensalism One species benefits

The other is not hurt or helped

Organisms and Energy

All the energy on Earth comes from the sun!!

Autotroph Organisms that use

the energy from the sun to produce their own food.

(producers)

Heterotroph Consumes other organisms as food

source. 3-Types

1. Herbivores

2. Carnivores

3. Scavengers and decomposers

Herbivores Heterotrophs that

consume plants only.

Ex: cows, deer, rabbits…

(First order consumers)

Carnivores Heterotrophs that

consume other animals.

Ex: Humans, cats…

(Second… order consumers.)

Scavengers Feed on dead

organisms.

Ex: vultures

Decomposers Break down dead

plants and animals.

Ex: Bacteria and fungus

How does energy flow through the ecosystem???

In ONE direction only

Sun-Producers-Consumers-Decomposers- Released as heat

Sun-Producers-Consumers-Decomposers- Released as heat

Autotrophs

First-order heterotrophs

Third-order heterotrophs Second-order

heterotrophs

Decomposers

Food Chain Simplest exchange of

energy.

Food Web: Interconnected, overlapping food chains

Food Web

Ecological Pyramids

Shows how energy flows through the ecosystem

Energy Pyramid Shows how energy decreases by 90% at each trophic level.

Only 10% of the energy is passed onto the next level.

Energy Pyramid Organisms at the

bottom of the pyramid are more numerous than at the top.

Different Types of Pyramids

Nutrients Nutrients cycle

through the ecosystem, never disappearing.

nutrients

nutrients

nutrients

Water Cycle 3 parts…

1. Evaporation

2. Condensation

3. Precipitation

Water Cycle

Nitrogen Cycle 2 Parts…

1. Nitrification

2. Denitrification

Carbon Cycle