Microbiology Practice Vocabulary

A set of 50 vocabulary flashcards derived from microbiology notes covering metabolism, microbial growth, and methods of microbial control.

Metabolism

The sum of all chemical reactions in a cell, consisting of catabolism and anabolism.

Catabolism

The process that breaks down molecules and releases energy.

Anabolism

The process that builds molecules using energy.

Enzymes

Biological catalysts that speed up chemical reactions.

Activation energy

The energy barrier that enzymes lower by providing an alternative pathway requiring less energy.

Apoenzyme

An inactive protein portion of an enzyme that lacks its cofactor.

Holoenzyme

An active enzyme that includes its cofactor or coenzyme.

Competitive inhibition

A process where an inhibitor competes with the substrate for the enzyme's active site.

Noncompetitive inhibition

A process where an inhibitor binds to a site other than the active site and changes the enzyme's shape.

Feedback inhibition

A mechanism where the end product of a metabolic pathway inhibits an earlier enzyme.

Oxidation

The loss of electrons from a molecule or atom.

Reduction

The gain of electrons by a molecule or atom.

Aerobic respiration stages

The metabolic process consisting of Glycolysis, the Krebs cycle, and the Electron Transport Chain (ETC).

Glycolysis location

The cytoplasm of the cell.

Krebs/ETC location

The mitochondria within the cell.

Purpose of ETC

The production of ATP through the process of chemiosmosis.

ATP synthase

The enzyme responsible for making ATP.

Fermentation

The anaerobic regeneration of $NAD^+$.

Aerobic respiration vs. fermentation

Aerobic respiration uses oxygen and produces more ATP, while fermentation does not.

Autotroph

An organism that makes its own organic compounds from $CO_2$.

Heterotroph

An organism that obtains carbon from organic compounds.

Microbial growth

The increase in the number of cells.

Psychrophiles

Microbes that are cold-loving.

Mesophiles

Microbes that thrive at moderate temperatures.

Thermophiles

Microbes that are heat-loving.

Acidophiles

Microbes that are acid-loving.

Alkaliphiles

Microbes that are alkaline-loving.

Halophiles

Microbes that are salt-loving.

Obligate aerobe

An organism that requires oxygen to grow.

Obligate anaerobe

An organism that cannot tolerate the presence of oxygen.

Facultative anaerobe

An organism that can grow either with or without oxygen.

Microaerophile

An organism that needs oxygen at low concentrations.

Lag phase

The phase of microbial growth involved in preparation for growth.

Log phase

The phase of microbial growth characterized by rapid cell division.

Stationary phase

The growth phase where the rate of cell growth equals the rate of cell death.

Death phase

The phase of growth where cell deaths exceed the formation of new cells.

Direct counting methods

Methods used to count microbes such as plate count and microscopy.

Indirect methods

Methods for estimating microbial growth such as turbidity and metabolic activity.

Selective media

Growth media that inhibits the growth of some microbes while allowing others to grow.

Differential media

Media used to distinguish between different types of microbes.

Enriched media

Media containing extra nutrients for the growth of fastidious microbes.

Asepsis

The absence of pathogens.

Disinfectant

A chemical used for controlling microbes on nonliving surfaces.

Antiseptic

A chemical for controlling microbes on living tissue.

Nosocomial infection

An infection that is hospital-acquired.

Autoclaving

The most effective method of microbial control.

Thermal death point

The lowest temperature required to kill all microbes in $10\,min$.

Thermal death time

The minimum time required to kill all microbes at a given temperature.

Decimal reduction time

The time required to kill $90\%$ of a microbial population.

Pasteurization

The use of heat to reduce the number of pathogens.