Ecology

The study of interactions between organisms and their environments.

Biotic Factors Bio = life Biotic factors – All living organisms in a

biosphere Examples: Plants, Animals

Abiotic Factors Nonliving factors in an environment Examples:

Air currents Temperature Moisture Light Soil

Ecological Organization of Life

Organisms

Populations

Communities

Ecosystems

Biosphere

Organism Population An individual form of

life that is capable of carrying out the life processes.

A group of individuals of the same species is a population.

Community Ecosystem Populations of

different species interact to form communities.

A community and its abiotic environment are an ecosystem

Biosphere The living organisms

and their environment composing the biosphere.

Feeding Relationships Autotroph: An organism that synthesizes its

energy from photosynthesis. Heterotroph: An organism that cannot

synthesize its own food. Carnivores: Meat eaters Omnivores: Meat and plant eaters Herbivores: Plant eaters Decomposers: Breakdown dead and decaying

organisms.

Trophic Relationships Autotrophs 1st level consumers (herbivores) 2nd level consumers 3rd level consumers 4th level consumers

(top predators)

Food Chain The transfer of food

energy from one organism to another in an ecological community.

A food chain begins with a producer.

Food WebA series of interrelated food chains in an ecosystem.

RULE OF 10 Only 10% of energy is transferred from

one trophic level to the next. Example:

It takes 100 kgs of plant materials (producers) to support 10 kgs of herbivores

It takes 10 kgs of herbivores

to support 1 kg of

1st level predator

Pyramid of Numbers

Symbiosis = “Living Together”

Examples of Parasitism (+/-)

Examples of Mutualism (+/+)

Commensalism (+/0)

Water Cycle

Evaporation Transpiration Precipitation Runoff Groundwater

Carbon Cycle

Combustion Photosynthesis Respiration Decomposition Fossil fuels

Nitrogen Cycle

Atmospheric nitrogen Runoff Fertilizers Decomposition Nitrogen fixing Synthesis of

amino acids

Niche vs. Habitat The role and location

of an organism within an ecological community.

The environment where a plant or animal lives.

Biomes A large community of plants and animals

that occupies a distinct region. Biomes can be:

1. Terrestrial

2. Aquatic

Biomes of the World

Tropical Rain Forest

Savanna

Desert

Grassland

Deciduous Forest

Tundra