Microbial Cell Biology

These flashcards cover essential terminology and concepts related to microbial cell biology, including cellular structures, types of cells, and fundamental biological processes.

Prokaryotic Cells

Cells that lack a membrane-bound nucleus and organelles, primarily consisting of bacteria and archaea.

Eukaryotic Cells

Cells that contain a membrane-bound nucleus and organelles, including fungi, protists, and algae.

Gram-positive

Bacteria characterized by a thick peptidoglycan layer in their cell wall and no outer membrane.

Gram-negative

Bacteria characterized by a thinner peptidoglycan layer and an outer membrane that can contain lipopolysaccharides.

Plasmids

Small, circular DNA molecules independent of chromosomal DNA, often carrying genes that provide a selective advantage, such as antibiotic resistance.

Flagellum

A long, whip-like structure that aids in bacterial motility.

Nucleoid

The irregularly-shaped region within a prokaryotic cell that contains the cell's genetic material.

Endosymbiotic Theory

The theory that eukaryotic cells evolved from a symbiotic relationship between large and small prokaryotic cells, leading to organelles like mitochondria and chloroplasts.

Cytoplasmic Membrane

The barrier that separates the interior of a cell from the external environment, composed of a phospholipid bilayer.

Chemotaxis

The movement of an organism in response to a chemical stimulus.

Ribosomes

Molecular machines within cells that synthesize proteins from amino acids.

Lysosome

An organelle containing digestive enzymes that break down waste materials and cellular debris.

Cytoskeleton

A network of fibers within the cell that provides structure and shape and aids in cell division and transport.

Chloroplasts

Organelles found in plant cells and some protists that conduct photosynthesis.

Mitochondria

Organelles that generate ATP through cellular respiration.

Pilus (pili)

Hair-like structures on the surface of bacteria that assist in attachment or the transfer of genetic material.

Capsule

A polysaccharide layer outside the cell wall that protects bacteria from phagocytosis and helps prevent recognition by the immune system.

Endospore

A dormant, tough, and non-reproductive structure produced by some bacteria to resist harsh conditions.

Teichoic Acid

A component of Gram-positive bacterial cell walls that plays a role in maintaining structural integrity and regulating ion movement.

Fimbriae

Short, hair-like appendages that help bacteria adhere to surfaces.

Magnetosomes

Organelles containing magnetic iron crystals that allow bacteria to align along magnetic fields.

Outer Membrane

A lipid bilayer that is part of Gram-negative bacteria protecting against certain substances.

Hydrophilic

Having an affinity for water; components that are polar and can interact with water.

Hydrophobic

Repellent to water; components that are non-polar and do not interact with water.

Eukaryotic Organelles

Specialized structures within eukaryotic cells that perform distinct functions, such as mitochondria, ribosomes, and lysosomes.