Bacteria—these are one-celled organisms lacking a nucleus and having a plasma membrane cell wall. Bacteria can be aerobes or anaerobes; only a small percentage of bacteria are pathogenic. They store most of their DNA in one long looping molecule (chromosome), but can also contain plasmids, which are small, circular, doublestranded DNA molecules that replicate independently from their host (see Plasmid, below).
Bacteriophage (phage)—a virus that attacks or colonizes a bacterium. Bacteriophages are specific; one type of phage will attack only one species of bacteria.
Biosafety—in activities involving life forms or their parts, the observance of precautions and preventive procedures that reduce the risk of adverse effects.
Biosecurity—activities designed to secure for humans, animals, and plants freedom from possible hazards attending biological activities, such as research, development, testing, and applications; measures taken by governments to guard against damage that may be brought about by accidental or intentional exposure to biological agents or toxins.
Biotechnology—a collection of processes and techniques that involve the use of living organisms, or substances from those organisms, to make or modify products from raw materials for agricultural, industrial, or medical purposes.
Brucellosis—caused by any of a number of species of the genus Brucella; the species that most often cause disease in humans are Brucella suis and Brucella abortus.