Chapter 15: Microbes and Prokaryotes

Vocabulary practice flashcards covering microbial life, prokaryotic anatomy, reproductive and survival mechanisms, metabolic categories, and nutrient cycling from Chapter 15.

Microbe

A microscopic single-celled organism.

Human microbiome

The complete collection of microbes that live in and on our cells and bodies that affects human health, brain, and body odor.

Citizen science

Research that is assisted by members of the public.

Capsule

An additional protective layer that surrounds the cell wall in prokaryotes.

Pili

Hairlike projections that cover the surface of many bacteria and archaea.

Flagellum

A long whiplike structure that assists some prokaryotes in locomotion.

Thermopile

A prokaryote, usually an archaean, that can live in extremely hot environments.

Halophiles

A prokaryote, usually an archaean, that lives in salty environments.

Quorum sensing

A system of cell-to-cell communication used by prokaryotes that enables them to sense and respond to other bacteria in the area.

Binary fission

Cell division in which a cell simply divides into two halves, resulting in daughter cells being identical to parent cells.

Sporulation

The formation of thick-walled dormant structures called spores.

Aerobes

Prokaryotes that need oxygen to survive.

Anaerobes

Prokaryotes that do not need oxygen to survive.

Methanogen

An anaerobic archaean that feeds on hydrogen and produces methane gas as a product.

Fermentation

A metabolic pathway by which most anaerobic organisms extract energy from organic molecules, enabling organisms to generate ATP anaerobically.

Heterotroph

A metabolic consumer; an organism that obtains energy by taking it from other sources.

Autotroph

A metabolic producer; an organism that makes its own food.

Chemoheterotroph

A metabolic consumer; an organism that obtains energy by taking it from other sources.

Photoheterotroph

A metabolic consumer; an organism that obtains energy by taking it from other sources.

Photoautotrophs

Organisms that absorb the energy from sunlight and take in carbon dioxide to conduct photosynthesis.

Chemoautotroph

A metabolic producer; an organism that makes food on its own.

Nitrogen fixation

The process carried out by bacteria of taking nitrogen gas from the air and converting it to ammonia for plants.

Nutrient cycling

The process by which decomposers break down dead organisms or waste to release chemical elements locked in biological material to return it into the environment.