Bacterial Cell Structures and Functions

These flashcards cover key vocabulary and concepts related to the structures and functions of bacterial cells, including cell walls, reproduction methods, and metabolic processes.

Peptidoglycan

A polymer that makes up the cell wall in bacteria, composed of sugars and amino acids.

Gram-positive bacteria

Bacteria with thick peptidoglycan layers in their cell walls that retain the crystal violet dye during Gram staining.

Gram-negative bacteria

Bacteria with a thinner peptidoglycan layer and an outer membrane; they do not retain the crystal violet dye during Gram staining.

Periplasmic space

The space between the inner and outer membranes in Gram-negative bacteria, containing enzymes and proteins.

Endospore

A highly resistant, dormant structure formed by certain bacteria, allowing them to survive extreme conditions.

Binary fission

The primary method of bacterial reproduction where one cell divides into two identical cells.

Plasmid

A small, circular DNA molecule within bacteria that is separate from chromosomal DNA and can carry genes for antibiotic resistance.

Active transport

The movement of molecules across a membrane against their concentration gradient, requiring energy.

Facultative anaerobes

Bacteria that can grow in both the presence and absence of oxygen.

Heterotrophic bacteria

Bacteria that obtain their food by consuming organic compounds, as opposed to making their own food.

Spirilla

A type of bacteria with a spiral shape.

Coccus

A spherical-shaped bacterium.

Bacillus

A rod-shaped bacterium.

Pleomorphic

Bacteria that can have more than one shape or form.

Snapping division

A type of bacterial division where the new cell wall forms but the cells remain partially attached.

Lipopolysaccharide

A molecule consisting of a lipid and a polysaccharide that forms the outer membrane of Gram-negative bacteria.

Osmotic pressure

The pressure required to prevent water from diffusing into a cell by osmosis, which bacteria must manage to prevent bursting.

Porins

Protein channels in the outer membrane of Gram-negative bacteria that allow the passage of small molecules.

Antibiotic resistance

The ability of bacteria to survive treatment with drugs that usually eliminate bacteria.

Archaea

Microorganisms that are similar to bacteria but genetically and biochemically distinct; can be extremophiles.

Halophiles

Archaea that thrive in high-salt environments.

Glycolysis

A metabolic pathway that converts glucose into pyruvate, yielding energy in the form of ATP.

Transporter

A protein that facilitates the movement of ions or molecules across a membrane.