Ecology UnitEcology Unit

A: organization of the Environment A: organization of the Environment B: Interactions in the Environment B: Interactions in the Environment C: Humans and the Environment C: Humans and the Environment

Vocabulary:

1. Ecology- the branch of biology that deals with the interactions between organisms , and the relationships between the organisms and the environment.

2. Population- members of the same species living in a given area.

3. Community- includes all populations in a given area.

4. Ecosystem- all living things and the physical environment that they live in.

5. Biosphere- the portion of the Earth where life exists.

Main Idea- The interactions between organisms and the Main Idea- The interactions between organisms and the relationships between the organisms and the environment. relationships between the organisms and the environment.

Requirements for a Stable Ecosystem:

A constant supply of energy (SUN). Living organisms that can turn energy from the sun into

organic compounds. Material must be recycled between organisms and the

environment.

(Ex.- an aquarium is a stable, balanced ecosystem.)

Abiotic Factors:

The non-living parts of the environment. Abiotic factors are:

Air Water Soil Light (Sun) Temperature Minerals

Biotic Factors:

The living things that directly or indirectly affect the ecosystem.

Examples of Biotic Factors are: Producers- organisms that make their

own food. Consumers- organisms that get their food

from other sources. Decomposers- break down, and recycle,

dead and decaying organisms.

Habitats and Niches:

A habitat is the place in and ecosystem where an organism lives.

A Niche is the role or job an organism has in an ecosystem.

Biodiversity:

Biodiversity is the diversity of species on the Planet as a result of the evolutionary process.

Biodiversity increases the chance that at least some species will survive in the face of large environmental changes.

Biodiversity also increases the stability of an ecosystem and guarantees the availability of a variety of genes (large gene pool).

Interactions in the Environment:

Food relationships involve interacting organisms.

Organisms are either Autotrophs (organisms that make their own food- plants) or

Heterotrophs (organisms that get their food from other sources).

There are 3 types of Heterotrophs: Herbivore- eat plants Carnivore- eat meat Omnivore- eat plants and meat

Carnivores can be further divided into 3 groups: Predators- carnivores that kill and

consume their prey. Prey- the animals that are killed and

eaten. Scavengers- eat the dead animals

they find that are left over from the predators.

Symbiotic Relationships:

Symbiosis involves organisms of different species living together in close association with at least one of the organisms benefiting.

Mutualism- both organisms benefit

Commensalism- one organism benefits, the other is not harmed.

Parasitism- one organism benefits (parasite), the other organism is harmed (host).

Food Chains:

Producer Primary Consumer Secondary Consumer

**Decomposers are found at every level of a food chain.

Food Webs:

A food web is made up of many interconnecting food chains.

Energy Pyramid:

The Sun is the primary source of energy in an ecosystem.

Energy is lost at each level on the energy pyramid.

The greatest amount of energy is found at the producer level (bottom).

The higher up in the pyramid the less energy.

Material Cycles:

Materials must be recycled between the living and the non-living environment.

There are 3 Material Cycles: Oxygen-Carbon Dioxide Cycle-

(photosynthesis, cellular respiration)

Nitrogen Cycle- dead and decaying organisms, nitrogenous wastes are converted.

Water Cycle- evaporation, condensation, and precipitation.

Competition:

Competition occurs when there is a struggle for the same limited resources.

Competition may eventually cause one species to become extinct.

Competition usually establishes one species per niche in a community.

Humans and the Environment:

Humans differ from all other kinds of organisms in their ability to change the environment.

Human activities upset various natural systems and have negative effects on the biotic and abiotic environment.

Some changes in the environment can be repaired, some can not.

In order for humans to survive as a species they must interact with many different forms of life, as well as, the non-living parts of the environment.

The abiotic environment provides us with essential components upon which our survival depends.

Acid Rain Greenhouse Effect Air Pollution Water Pollution Global Warming

These are just some examples of negative effects that mankind has had on the environment. These changes are caused by advances in technology.

Environmental Pollution:

A pollutant is something that is put into the air, water, or soil that makes it dirty and unfit for living things.

Pollutants are toxic (poisonous). Pollutants are by products of technology.

The ways in which we change our physical environment will ultimately determine the survival of all living things and our own species.

Negative Human Activities:

Over-hunting Importing of organisms Exploitation Poor land management Deforestation Improper waste disposal (biodegradable) Use of biocides (pesticides, herbicides) Poaching

Conservation of Natural Resources:

Conservation involves the protection and wise use of our natural resources.

Natural resources include the basic things in the natural world (soil, air, water, energy, wildlife, and open space).

Renewable resources are able to be reused or replaced.

Nonrenewable resources cannot be replaced. Recycling resources that are nonrenewable is

recommended to conserve them. Erosion causes much soil to be lost because it

is worn away by wind and water. Wildlife preservation is efforts to help

endangered species and to protect other forms of wildlife.

Laws to protect wildlife continue to be passed to help protect wildlife in danger of becoming extinct.