18.1

Ecosystems

contains all the nonliving and living parts of the environment in a given area

Example on Ecosystem :

  • The Garden

Abiotic factors

are the Nonliving parts of an Ecosystem

They include :
Sunlight, water, soil and air

Habitats

is the place within an ecosystem that provides the biotic and abiotic factors an organism need to survive and reproduce.

Biotic factors

are The living or once-living parts of an ecosystem

They include :
Living organisms, wastes produced by living organisms and the decayed remains of dead organisms

example of habitat :A habitat for dragonflies includes plants that grow in shallow water.

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Populations

is all the organisms of the same species that live in the same area at the same time

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Communities

It is all the populations living in an ecosystem at the same time

Niche

It is the way a species interacts with abiotic and biotic factors to obtain food, find shelter and fulfill other needs

Predation

Prey

Predator

Predation

is an organism that hunts and kills other organisms for food

is an organism caught and eaten by a predator

It is the act of predator feeding on its prey

Symbiosis

is a close, long-term relationship between two species that usually involves an exchange of food or energy

2- Commensalism

3- Parasitism

1- Mutualism

both species benefit

one species benefit other species
is neither harmed nor benefited

one species
( the parasite ) benefits other species
( the host ) is harmed

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Competition

describes interactions between two or more organisms that need the same resource at the same time

Carrying Capacity & Overpopulation

Carrying capacity: it is the largest number of individuals of one species that an ecosystem can support over time.

If a population exceeded its carrying capacity the area will become
over-populated