Bacterial growth 2019 (1)

Microbial Growth

An increase in the number of microorganisms or cells in a population.

Metabolism

Chemical processes that occur within a living organism to maintain life, including the conversion of food to energy.

Binary Fission

A form of asexual reproduction where a single cell divides into two identical daughter cells.

Lag Phase

The initial phase of bacterial growth where there is no increase in cell number, but metabolic activity is high.

Log Phase

The phase of rapid cell division in bacterial growth, characterized by exponential increase in cell number.

Stationary Phase

A phase in microbial growth where the rate of cell division equals the rate of cell death, resulting in a stable population.

Death Phase

The phase characterized by a decline in the number of viable cells due to nutrient deprivation and accumulation of toxic waste.

Generation Time

The time taken for a bacterial population to double in number.

Nutrient Concentration

The amount of nutrients available in the environment which affects the growth rate of microorganisms.

Pseudomonas aeruginosa

A type of bacterium known for its resistance to antibiotics and its role in various infections.

Acidophiles

Organisms that thrive in acidic environments, typically at pH values below 5.5.

Alkaliphiles

Microorganisms that prefer alkaline conditions, typically growing best at pH levels above 9.

Obligate Aerobes

Microorganisms that require oxygen for growth.

Facultative Anaerobes

Microorganisms that can grow with or without oxygen, but prefer oxygen when available.

Microaerophiles

Organisms that require oxygen levels lower than that of the atmosphere for growth.

Water Activity (Aw)

A measure of the availability of water in a substance for microbial growth.

Halophiles

Microorganisms that thrive in high salt concentrations.

Plasmolysis

The process where a cell's plasma membrane shrinks away from the cell wall due to loss of water in a hypertonic environment.

Glycocalyx

A sticky layer consisting of polysaccharides and glycoproteins that surrounds the cell wall of some bacteria, aiding in adhesion and protection.

Obligate Anaerobes

Microorganisms that cannot grow in the presence of oxygen.

Aerotolerant Anaerobes

Microorganisms that do not use oxygen but can tolerate its presence.

Thermophiles

Organisms that thrive at elevated temperatures, typically between 45-80°C.

Psychrophiles

Microorganisms that grow optimally at low temperatures, typically below 15°C.

Biosafety Levels (BSL)

Containment levels for laboratories that handle pathogens, with BSL-1 being the lowest and BSL-4 the highest.

Biofilm

A complex community of microorganisms adhering to surfaces, encased in a protective extracellular matrix.

Endospores

Highly resistant structures formed by some bacteria to survive unfavorable conditions.

Culture Media

Nutrient solutions used to grow microorganisms in a laboratory.

Incubation Period

The time taken for microbes to grow and multiply in culture after inoculation.

Antibiotic Resistance

The ability of microorganisms to survive and proliferate despite the presence of antibiotics.

Symbiotic Relationships

Interactions between different species that can be beneficial, neutral, or harmful to one or both organisms.

Pathogenicity

The ability of an organism, particularly a microorganism, to cause disease.

Virulence Factors

Molecules produced by pathogens that contribute to the pathogenicity and enable them to achieve colonization, immune evasion, and tissue damage.

Antimicrobial Agents

Substances that kill or inhibit the growth of microorganisms, including antibiotics and antifungals.

Protozoa

Single-celled eukaryotic organisms that can be free-living or parasitic.

Fungi

Eukaryotic organisms that include yeasts, molds, and mushrooms, characterized by cell walls made of chitin.

Bacteriophage

A virus that infects and replicates within bacteria, sometimes used in phage therapy to treat bacterial infections.

Infection Control

Preventive measures to reduce or eliminate the risk of infection, important in healthcare settings.

Antiseptics

Chemical agents applied to living tissues to reduce the risk of infection, typically by killing or inhibiting pathogens.

Vaccination

The process of introducing a vaccine into the body to stimulate an immune response against specific pathogens.