The Prokaryotic Cell

Flashcards covering key concepts and vocabulary from the lecture on prokaryotic cells.

Cell Theory

Cells are fundamental units of life; all living organisms are composed of cells; all cells come from preexisting cells.

Nucleoid

The region in prokaryotic cells where the chromosome is organized, not enclosed by a membrane.

Surface Area-to-Volume Ratio

A ratio that limits the size of cells; as cells grow, their volume increases faster than their surface area.

Transcription

The process of copying a segment of DNA into RNA in prokaryotic cells, often coupled with translation due to the absence of a nucleus.

Peptidoglycan

A polymer consisting of disaccharides cross-linked with amino acids that forms the cell wall of bacteria.

Gram-positive Bacteria

Bacteria with a thick peptidoglycan layer that stain dark purple.

Gram-negative Bacteria

Bacteria with a thin peptidoglycan layer and an outer membrane that stain light pink.

Flagella

A long, whip-like structure made of protein that aids in the movement of prokaryotic cells.

Pili and Fimbriae

Hair-like structures on bacteria that aid in attachment; pili are longer, while fimbriae are short and numerous.

Cytoskeleton

A network of protein filaments in prokaryotic cells that functions in cell division, movement, and maintaining cell shape.

Comparison of Bacteria and Archaea

Bacteria have peptidoglycan in their cell walls; Archaea do not and have ether-linked membrane lipids.

Endosymbiosis Theory

The theory that eukaryotes evolved from a symbiotic relationship between an archaeal host and bacterial cells.

Eukaryotes

Organisms composed of cells with membrane-enclosed organelles, including protists, plants, fungi, and animals.