ecology

Ecosystem Structure

○ Abiotic vs. Biotic Components

■ Abiotic ● Nonliving components of Earth ○ Eg: Atmosphere, Hydrosphere, and Lithosphere

■ Biotic ● Living components of Earth ○ Eg: Animals, plants, fungi, protists, and bacteria which form the biosphere ○

● Types of Ecosystems

○ Classifications

■ Blending ● The biomes blend into each other ● There are no distinct boundaries

■ Ecotones ● A transitional area where two biomes meet

■ Ecozones/Ecoregions ● Small regions within ecosystems that have similar physical features ■

Interactions of Organisms with the Environment

■ Population ● A group of organisms of the same species

■ Community ● Populations of different species that occupy the same geographic area ● Every species occupies a habitat and has an ecological niche

■ Habitat ● The area or environment where an organism lives, or where an ecological community occurs

■ Ecological Niche

● The role and position a species has in its environment ● Includes how a species uses biotic and abiotic resources in its environment, where the species lives, and what it eats ○ Interactions of Organisms Among Each Other

■ Competition ● Occurs when two individuals are competing for resources in the environment ■

Edge Effects:

● Ecotones have a great amount of species diversity and biological density ● Some species only live on the edge of certain habitats

○ Symbiotic Relationships ○ Close, prolonged associations between two or more different organisms of different species

■ Types of Symbiotic Relationships

**● Mutualism ○ Both organisms receive beneficial properties from their relationship ■ Eg: pollinators benefit from feeding on plant nectar, and plants benefit from pollinators moving their pollen from plant to plant

** ●Commensalism ○ One organism benefits in the relationship and the other are neither harmed nor benefited ■ Eg: Barnacles are sedentary crustaceans that sweep the surrounding water for small, free-floating organisms. They often grow attached to scallop shells, which has almost no effect on the scallop

Resource Partitioning ● Occurs when species can coexist and share resources without any conflict ■ Predation ● Occurs when one species feeds on another

● Drives changes in population size ○ Eg: ■ Cat & Mouse ■ Polar Bear & Seals ■ Lions & Wildebeests ■ Great White Shark & Elephant Seals

**● Parasitism ○ One organism benefits by harming the other organism ■ Eg: Mistletoe is a flowering plant that grows attached to, and within, the vascular system of a tree or shrub. This helps the mistletoe but harms the tree

○ Bioenergetics - The study of how energy flows through living organisms ■ All energy on Earth comes from the Sun ■ Photosynthetic organisms use solar energy to turn CO2 and H2O into carbohydrates ● Also releases O2 ■ Biological macromolecules store energy in their chemical bonds

● Energy Flow ○ Cell Respiration - Occurs when autotrophs make ATP (adenosine triphosphate) from carbohydrates and other biomolecules in a complex series of reactions

Page updated

Report abuse