Prokaryotes: Bacteria and Archaea

Flashcards covering key vocabulary and concepts related to prokaryotes, their characteristics, and their significance.

Prokaryotes

Single-celled organisms without a nucleus, categorized into Bacteria and Archaea.

Bacteria

A domain of prokaryotic cells characterized by peptidoglycan in their cell walls.

Archaea

A domain of prokaryotic organisms that lack peptidoglycan in their cell walls and have unique biochemistry.

Binary Fission

The process by which prokaryotes reproduce asexually, resulting in two identical daughter cells.

Transformation

A mode of genetic recombination in bacteria where foreign DNA is taken up from the environment.

Transduction

The transfer of bacterial DNA from one bacterium to another via bacteriophages.

Conjugation

A process of genetic exchange between bacteria through direct contact and DNA transfer.

Gram-positive bacteria

Bacteria that have a thick peptidoglycan layer in their cell wall, retaining the Gram stain.

Gram-negative bacteria

Bacteria with a thinner peptidoglycan layer and an outer membrane, often more resistant to antibiotics.

Antibiotic resistance

The ability of bacteria to survive and multiply despite the presence of antibiotic drugs.

Capsule

A sticky layer composed of polysaccharides or proteins that surrounds some prokaryotic cells, aiding in adherence and defense.

Fimbriae

Hair-like structures on the surface of prokaryotes that help them adhere to surfaces.

R Plasmids

Plasmids that carry genes providing resistance to antibiotics.

Exotoxins

Toxins secreted by bacteria that can cause disease, even in the absence of the bacteria itself.

Endotoxins

Lipopolysaccharides released only when bacteria die and their cell walls break down, often causing fever and shock.

Mutualistic bacteria

Bacteria that beneficially inhabit the human intestines, aiding in digestion.

Facultative anaerobes

Prokaryotes that can survive with or without oxygen, utilizing aerobic respiration or fermentation.

Photoautotrophs

Organisms that obtain carbon from CO2 and energy from light.

Chemoheterotrophs

Organisms that derive carbon and energy from organic compounds.