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unicellular organisms that lack a nucleus


rod-shaped prokaryotes


Spherical prokaryotes


Spiral and corkscrew-shaped prokaryotes


heterotrophic prokaryotes that must take in organic materials for both energy and supply of carbon


heterotrophic prokaryotes use sunlight for energy, photosynthesis, but also need organic compounds as a carbon source


autotrophic prokaryotes that use light energy to convert carbon dioxide and water to carbon compounds and oxygen


prokaryotes that make organic carbon molecules from carbon dioxide. do not require lights a source of energy

obligate aerobes

organisms that require a constant supply of oxygen in order to survive

obligate anaerobes

organisms that live in the absence of oxygen

facultative anaerobes

organisms that can survive with or without oxygen

binary fission

type of asexual reproduction in which an organism replicates its DNA and divides in half, producing two identical daughter cells


a hollow bridge forms between two bacterial cells and genes move from one cell to the other


type of spore formed when a bacterium produces a thick internal wall that encloses its DNA and a portion of its cytoplasm

nitrogen fixation

the process of converting nitrogen gas into a form plants can use

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