MICROBIOLOGY GLOSSARY

aerobes - organisms that thrive in well-aerated environments

anaerobe - organism that wants very little or no oxygen

autotrophs - organisms that need no preformed organic foods

bacterial endospores - see endospores

bacteriophage - virus (phage) that infects a bacterium

chemotrophs - organisms that derive energy from inorganic reactions

constitutive - enzyme always synthesized and ready

endospore - seed-like structure; formed to preserve life when conditions turn bad

eukaryotic - cell has nucleus; divides through mitosis
The cytoplasmic membrane of prokaryotes is fundamentally similar to that of a eukaryotic cell. The variety of proteins in the cytoplasmic membrane in prokaryotes is greater because of the significantly greater number of functions performed by it. As with eukaryotes, the membrane controls the permeability of the cell and is the major site of energy metabolism. In bacteria, either the electron transport system or the site of photosynthetic energy metabolism is located in the cytoplasmic membrane. The ribosomes of the prokaryotes are the site of protein synthesis. Many prokaryotes are immotile, but some have either a single flagellum or multipole flagella as their means of locomotion.

facultative - prefers but not absolute, e.g., facultative anaerobe

flow cytometer - instrument with a tiny orifice through which particles (such as bacteria) flow through one at a time. As they pass through a laser beam, biochemicals may be determined on a per cell basis.

heterotrophs - organisms that must have carbon-energy compounds

inducible - enzyme not synthesized or activated until needed

nematodes - tiny worms; some are eaten by fungi

obligate - absolute requirement, e.g., obligate aerobe

pathogens - organisms that cause disease

phage - viruses for microorganisms

photosynthesis - use of light to carry out reductive biochemical processes necessary for life. Pigments capture light energy in much the same way as an antenna captures a radio or tv signal. This drives biochemical reactions. The overall effect may be summarized as water plus carbon dioxide are converted to biochemicals.

prokaryotic - no organized nucleus
The components of a typical prokaryotic cell are a cell wall, a cytoplasmic membrane, a single molecule of DNA, ribosomes and the cytoplasm. All other components, although they might be present, are essentially dispensable.

protozoa - tiny animals; most feed on microorganisms

yeast - eukaryotic organisms larger than most bacteria, commonly divides by budding