Glossary of terms

• Aerobic

Microorganisms requiring oxygen to grow

• Anaerobic

Microorganisms not requiring oxygen to grow

• Catalase

An enzyme present in some microorganisms that converts hydrogen peroxide to water and oxygen

• Cocci

Bacteria that are sphere shaped

• Coccobacilli

Bacteria that are short rod shaped

• Facultative anaerobic

Microorganisms that can grow in either aerobic or anaerobic conditions

• Flagella 

A flexible tail-like structure on some microorganisms that assist them in moving

• Gram negative

Bacteria that when Gram stained appear red

• Gram positive

Bacteria that when Gram stained appear purple

• Gram stain 

A staining technique that differentiates between classes of bacteria

• Indole 

A substance produced by some microorganisms

• Microaerobic

Microorganisms that require only small amounts of oxygen to grow

• Oxidase

An enzyme present in some microorganisms that allows them to combine oxygen (oxidation)

• Peritrichous flagella

Flagella present around the entire bacteria pH the measurement of the acidity or alkalinity of a substance

• Psychrotrophic

Bacteria capable of growing at temperatures below 7°C

• Rods

Bacteria that are rod-shaped

• Serotype

Bacteria within the same species that can be distinguished on the basis of their surface antigenic properties

• Spores

Spherical bodies produced internally by some bacteria, that are usually more resistant to heat and chemicals

• Water Activity

The amount of water available for growth of a microorganism