Levels of Biological Organization All the levels of biological organization will be introduced at the beginning of the year. These are the different levels at which you can study biology. If one level is effect by some sort of change, the change will have an effect on each of the levels in a related way (drought in the ecosystem, dehydration in the organism, cells lose water, etc). For unit 1, focus on the macroscopic levels (starting at organism and ending at biosphere).

Organelle Structures with particular functions with in cells Membrane-bound organelles are found in eukaryotic cells Examples include the mitochondria, chloroplast and nucleus

Cell Basic unit of all organisms Smallest living thing Simple cells are Prokaryotes and complex cells are Eukaryotes

Tissue A group of the same type of cells that work together to perform a specific function Examples of tissues in animals include muscle, bone, epithelial, and nervous tissue Plants and Fungi also have tissue

Organ A group of two or more tissues working together to perform a specific function Examples of organs in animals include the stomach, the heart, the brain, and the skin Plants also have organs such as roots, stems and leaves

Organ System Multiple organs that work together to perform a specific function Examples of organ systems in animals include the digestive, immune, and nervous system Plants also have organ systems (ex: vascular system)

Organism A living thing Anything that possesses all the characteristics of life Organisms can either be animals, plants, fungus, protists, bacteria or archae

Population A group of organisms, all of the same species, living in the same place at the same time These organisms can interbreed

Community A group of several populations living in the same place at the same time Communities make up food chains and food webs Communities only include the biotic (living) things

Ecosystem All of the biotic (living) and abiotic (non-living)factors interacting in the same place at the same time Biotic = living (ex: grass, snail, frog) Abiotic = nonliving (ex: rock, climate, landforms)

Biosphere The portion of Earth that supports life This includes high in the atmosphere to deep in the oceans We live in the biosphere

Biosphere The portion of Earth that supports life This includes high in the atmosphere to deep in the oceans We live in the biosphere