Studied by 0 people
Looks like no one added any tags here yet for you.
Gram-positive cell wall
A thick peptidoglycan layer that retains the Crystal Violet stain during Gram staining, appearing purple.
Gram-negative cell wall
A thin peptidoglycan layer surrounded by an outer membrane that does not retain the Crystal Violet stain, appearing pink or red.
Mycolic acid
A waxy substance found in the cell walls of Mycobacterium and Nocardia, providing resistance to desiccation and immune attacks.
Atypical cell walls
Cell walls that lack peptidoglycan, characteristic of Archaebacterium.
No cell wall
A characteristic of Mycoplasmas, such as Mycoplasma pneumoniae, which makes them resistant to antibiotics that target cell wall synthesis.
Endospore
A dormant, tough, and non-reproductive structure produced by some bacteria to survive extreme conditions.
Sporogenesis/Sporulation
The process by which a bacterial cell forms a spore, involving DNA replication and the formation of a protective coat.
Germination
The process by which an endospore becomes a vegetative cell under favorable conditions.
Exotoxins
Toxins released by bacteria into the surrounding environment, often composed of proteins.
Endotoxins
Components of the outer membrane of Gram-negative bacteria, released upon cell lysis, typically lipopolysaccharides.
Photoautotrophs
Organisms that obtain energy from sunlight and carbon from carbon dioxide.
Chemoheterotrophs
Organisms that obtain energy from organic compounds and carbon from the same or different organic compounds.
Facilitated diffusion
The process of passive transport of molecules across a cell membrane via specific transmembrane integral proteins.
Active transport
The movement of molecules across a cell membrane against their concentration gradient, requiring energy.
Mesophile
Bacteria that grow best at moderate temperatures, typically between 20-45°C.
Thermophile
Bacteria that thrive at high temperatures, usually above 45°C.
Psychrophile
Bacteria that prefer cold environments, typically between -5°C to 20°C.
Exponential growth
Growth pattern where the population size doubles at regular intervals.
OD (Optical Density)
A measure of how much light is absorbed by a suspension of cells, used to estimate cell concentration.
Filtration
A method of cell counting that uses filters to separate cells from liquids.
Direct Microscopic Methods
Techniques to count cells by observing them directly under a microscope.
Turbidity
A measure of the cloudiness of a solution, correlating with cell concentration.
Flow Cytometry
A technique that uses laser technology to count and analyze microscopic particles.
