Glossary

active site
Active Site

Active site – Location on an enzyme where chemicals are bound prior to enzyme assisted reaction.

Aerobic Respiration
Aerobic Respiration

Aerobic respiration – using oxygen as the final electron acceptor in the energy creating electron transport chain. Aerobic organisms must have access to oxygen gasses in order to survive.

anaerobic respiration
Anaerobic Respiration

Anaerobic respiration – using any inorganic molecule, besides oxygen, as final electron acceptor to create ATP in electron transport chain.

Antibiotic Resistance
Antibiotic Resistance

Antibiotic resistance – antibiotic resistance is a naturally occurring process where bacteria develop the ability to resist the effects of an antibiotic. Extensive use of antibiotics has increased the numbers of bacteria that have antibiotic resistance by removing competition from bacteria that are not resistant.

Antibiotics, Antimicrobials, Antiseptics
Antibiotics, Antimicrobials, Antiseptics

Antibiotics are medicines produced by ohter microorganisms that treat illness caused by bacterial infection in humans or animals. Antibiotics do not have any effect on viruses.


Antimicrobial products kill or slow the spread of microorganisms including bacteria, protozoans, fungi or viruses. Pesticides, disinfectants and antibiotics are all types of antimicrobials.


Antiseptics are a type of antimicrobial chemical that is generally less corrosive and can be safely used on living tissue, they are most often used in surgical or healthcare settings.

Antimicrobial Resistance
Antimicrobial Resistance

Antimicrobial resistance – antimicrobial resistance occurs when any kind of microorganism, bacteria, fungi, virus, etc. has grown tolerant to medicines or chemical compounds that should kill or incapacitate them.

bactericidal
Bactericidal

Bactericidal- Capable of killing bacteria

Bacteriostatic- Capable of inhibiting the growth or reproduction of bacteria

bacterium
Bacterium Bacteria

Bacterium/bacteria – bacteria are very tiny (micro) life-forms that are fully contained inside one living cell. Most bacteria are not harmful but some cause illnesses like strep-throat and are called pathogens.

beta lactams
Beta Lactams

Beta lactams – group of antibiotics that attack bacterial cell wall structural development, weakening the cell wall and causing cell death by lysis. This group includes penicillin, cephalosporins, carbapenems and monobactams.

binary fission
Binary Fission

Binary fission - type of cellular reproduction where one cell divides into two daughter cells each of which contain a complete copy of the parental genome.

biofilm
Biofilm

Biofilm – An accumulation of microorganisms growing on a surface. Common examples include plaque on teeth and pond scum. Some biofilms can have positive impacts on human health, while others can cause disease.

cell
Cell

Cell - The basic biological unit. All living organisms are made of cells, from single-celled microbes to blue whales.

cell
Cell Membrane

Cell membrane - lipid bilayer that protects the cell. It is difficult to pass due to its duel-nature, containing both hydrophobic and hydrophilic regions (like oil and water), few chemicals can readily pass through both regions.

cell
Cell Wall

Cell wall – a structure of the cell that can increase the strength and rigidity of the cell. Not all cells have cell walls but those that do will better maintain their shape and withstand osmotic effects.

cell
Chromosome

Chromosome – Coiled structure of highly compressed DNA, contains all of the hereditary genes of a cell.

community
Community

Community – group of organisms, includes many interacting species

conjugation
Conjugation

Conjugation – One of the mechanisms for horizontal gene transfer. In conjugation, DNA is directly transferred between bacterial cells via a conjugation pilus which is a hollow tube that connects two bacterial cells.

dna
DNA

DNA - Deoxyribonucleic acid is a double-stranded chain of nucleic acids or nucleotides that provide the genetic material of a cell.

dna replication
DNA Replication

DNA replication - cellular process to copy all of the genetic information contained in a cell prior to cellular replication.

drug resistance
Drug Resistance

Drug Resistance – Ability of a microbe to tolerate the effect of an antimicrobial drug or compound.

endospore
Endospore

Endospore - Cellular structure which some bacteria form in response to adverse conditions. The spore contains a copy of the cell’s DNA, but it is not an active cell and so it is resilient to most environmental conditions.

enteric
Enteric

Enteric – bacteria common in the intestines, members of the Enterobacteriaceae family.

enzyme
Enzyme

Enzyme – type of protein that catalyzes biochemical reactions, making them require less energy and take play more rapidly.

flagella
Flagella

Flagella - long extracellular structures used by some bacteria to move about in liquid environments.

foodborne disease
Foodborne Disease

Foodborne disease – disease that is caused by a pathogenic microbe consumed with food. These pathogens can originate anywhere along the food production chain but also may be transferred to the food due to contamination in the preparation area (i.e. kitchen) or by the food handler.

Fungi
Fungus

Fungus/fungi - Unlike bacteria, fungi are eukaryotic organisms, they can be single celled or multi-cellular and range in size from microbial molds and yeast to very large mushroom structures.

gene
Gene

Gene - Segment of DNA that codes for a specific protein and thereby induces specific cellular behaviors.

generation time
Generation Time

Generation time – the time it takes for a bacterial population to double, in optimal conditions this can be from minutes to hours for many microbes.

gram negative
Gram Negative

Gram negative - a term used to describe bacteria that do not retain a particular type of dye when it is injected into the bacteria cell. They do not retain the dye, because of their two-layered cell wall, which also makes them more resistant to antibiotics.

Gram Positive
Gram Positive

Gram positive - a term used to describe bacteria that retain a particular type of dye when it is injected into the bacteria cell. They retain the dye because of their single-layered cell wall, which is more easily penetrated by the dye, making them less resistant to antibiotics.

horizontal gene transfer
Horizontal Gene Transfer

Horizontal gene transfer – Bacteria have developed a mechanism called horizontal gene transfer that enables them to exchange portions of their DNA. Genes are more easily passed when bacteria are in close proximity, such as in digestive systems, organic wastes or biofilms.

lysis
Lysis

Lysis - This refers to the process of a cell wall breaking down, releasing cell contents to environment. Lysis usually occurs due to some sort of biochemical reaction. Penicillin functions well as an antibiotic, because it causes lysis in bacteria.

mechanisms of antibiotics
Mechanisms of Antibiotics

Mechanisms of Antibiotics – There are three principal mechanisms by which antibiotics can inhibit cell growth or kill bacterial cells. Cell wall and membrane synthesis and function; nucleic acid synthesis and function; protein synthesis.

mesophillic
Mesophilic

Mesophilic – a type 0f microorganism that grows best at moderate temperatures, similar to those inside most mammals, typically between 20° C and 45° C (about 70° to 115° f)

microbe
Microbe

Microbe - A living organism that is too small to be seen by the human eye without the aid of a microscope. Microbes are also known as microorganisms.

mutation
Mutation

Mutation -An uncorrected change in the DNA sequence that is made as a cell is copying its DNA before dividing. Mutations are a common occurrence and are responsible for genetic variations within species. Depending on where they occur, some mutations are passed on to the next generation while some are not, and some cause significant changes in an organism while others do not.

normal body flora
Normal Body Flora

Normal body flora - Not all bacteria is bad! Our body needs some types of bacteria to be healthy. These bacteria serve important functions, like helping digest food in our gut. Normal Body Flora is used as a term to generally refer to these sorts of useful or neutral microbes (bacteria or yeast) in our bodies.

nosocomial
Nosocomial

Nosocomial (naa-suh-kow-mee-uhl) - describes diseases which are endemic to, or originate in, hospitals. A nosocomial infection is typically not the problem that a patient first seeks treatment for, but rather one they encounter while in the hospital for some other treatment or procedure. Staph infections and MRSA are common nosocomial infectious.

pathogen
Pathogen

Pathogen - A pathogen is any foreign life-form or virus that can infiltrate the body’s defenses and cause illness—these include bacteria, viruses, fungi and protozoa.

cell
Plasmid

Plasmid – A small, circular section of DNA found mostly in bacterial cells that is not incorporated into the chromosome. Although plasmids exist within a cell, they replicate independently. Scientists are able to manipulate and isolate plasmids in order to introduce their genes to another organism.

resistance gene
Resistance Gene

Resistance gene – Antibiotic resistance genes are very small segments of DNA that grant a bacterial cell the ability to resist the effect of an antibiotic.

Selective Pressure
Selective Pressure

Selective pressure – Any external agent, predator, nutrient supply, disease or chemical that affects an organism’s ability to survive, giving any subset of the species with an adaption to improve survivability in the presence of the agent a competitive advantage.

Thermophile

Thermophile – A microbe that grows best in warm temperatures between 50° C and 80° C (roughly 120° to 175° F).

vaccine
Vaccine

Vaccine - Describes a technology by which non-dangerous forms of a pathogen (a weakened form; a related, but safe form; or a “killed” version of the disease) are injected into the body. Once there, they stimulate the body’s immune system without causing illness, thus providing immunity to the disease in a safe fashion.

virus
Virus

Virus - The smallest type of microbe. Unlike other microbes, viruses are not really living organisms as they do not have cells and cannot reproduce on their own. Instead a virus consists of proteins and genetic material that can induce a host cell to reproduce the virus on its behalf.