Ecology:

The interaction of organisms with the environment.

Population:

- all members of a single species in a given location

Background Vocabulary

Community:

-only living organisms – all populations together

- all living things

Ecosystem:

- living (organisms) with the non-living (water, soil oxygen, carbon dioxide, sunlight)

Abiotic Factor – Not living

Biotic Factor - Living

Biosphere:

- portion of earth where life exists

- composed of numerous ecosystems (earth)

Habitat:

- organisms home – where an organism lives

Niche:

- an organisms role in the environment

****organisms can occupy the same habitat , but not the same niche

Competition:

- two different organisms living in the same environment utilizing the same limited resources will compete (fight)

These birds are occupying the same habitat but not the same niche

An ecosystem is made up of abiotic and biotic factors.

An ecosystem is self-sustaining if:

- constant source of energy

- cycling of materials

Abiotic Factors (NON_LIVING):

- physical and chemical factors which affect an organisms ability to survive

- the non-living factors

- ex. Intensity of light - pH levels

- range of temperatures - supply of gases

- amount of moisture

Limiting Factors (Abiotic or Biotic):

- determine the types of organisms which may exist in an environment

- ex: abiotic factors are limiting factors

ex. If a body of water’s dissolved oxygen level is low, fish that need higher oxygen levels could suffocate and die.

Carrying Capacity:

- maximum size of a population that can be sustained in a given area.

- limited resources affect populations: food, water, shelter, etc.

- members of a species compete for these things.

Biotic Factors:

- all living things that affect the environment

Autotrophs or Producers:

- synthesize their own food (inorganic to organic)

- ex. Photosynthesis and chemosynthesis

Heterotrophs or Consumers:

- cannot synthesize their own food.

Decomposers:

-break down organic wastes and dead organisms to simpler ones. (Recycle nutrients in an ecosystem)

Types of Heterotrophs:

1- Saprophytes: heterotrophic plants, fungi and bacteria which live on dead matter.(Decomposers)

2. Herbivores: Plant eating animals

3. Carnivores: Meat eating animals

4. Omnivores: eat both plant and animals

Types of Carnivores:

1. Predators: animals which kill and consume their prey

2. Scavengers: animals that feed on dead prey

Food Chains and Food Webs

-Show the pathway of energy through living components

Food Chain:

- Transfer of energy from green plants through a series of organisms. Shows predator – prey relationships

Food Web: Interacting food chains

Food (Energy) Pyramid:

Producers: (plants) autotrophs – photosynthesis

Primary consumers: herbivores

Secondary consumers: carnivores

**omnivores can be primary or secondary

Decomposers: Recycle nutrients in ecosystem (Bacteria & Fungi)

**There is a decrease in the overall energy in each level as you move up the food chain, web or pyramid.

**There is more energy in the producer level than at the consumer level

Biomass:

- amount of organic matter

**Total mass of carnivores in a particular ecosystem is less than the total mass of the producers**

Symbiotic Relationships:

Symbiosis: Living together

1. Commensalism: (+,0) one organism is benefited and the other is unaffected. Ex. Barnacles on a whale

2. Mutualism: (+,+) both organisms benefit

3. Parasitism: (+, -) parasite benefits at expense of host

ex. Tapeworm, athletes foot

Succession:

- Replacement of populations/communities until a stable community is reached – takes a very long time

Pioneer Organisms:

- First organisms to inhabit a location (lichens & mosses)

Climax Community:

- Community in which populations remain stable

Biodiversity-

- wide variety of species

- a climax community contains a great deal of biodiversity

Pioneer Organism:

- first organisms to inhabit a given location

- ex. Lichens & Mosses

• Succession of a climax forest

• Living things modify the environment one community makes it more suitable for the next

• Pioneer organisms Climax Forest

• Climate changes, natural disasters, and human activity can alter this process, but succession will continue and restore the climax community

In a self-sustaining ecosystem, materials must be cycled among the organisms and the abiotic environment

**Materials are reused**

1. Carbon-Hydrogen-Oxygen Cycle:

- Involves the process of respiration and photosynthesis

2. Water Cycle:

- involves photosynthesis, transpiration, evaporation, condensation, precipitation, respiration, and excretion