Prokaryotic Profiles: The Bacteria and Archaea Flashcards
What are prokaryotes?
Cells without a true nucleus
How are prokaryotes different from eukaryotes?
DNA is packaged differently, their cell wall is not made with a phospholipid bilayer, they lack membrane-bound organelles
What is the structure of the bacterial cell?
Cell membrane, cytoplasm, ribosomes, cytoskeleton, one(or few) chromosomes, most also have cell wall, surface coating(glycocalyx)
What are some structures that not all prokaryotic cells possess?
Flagella, pili, fimbriae, outer membrane, plasmids, inclusions, endospores, intracellular membranes
What is pleomorphism?
Variability of cell shape in same species
Characteristics of coccus(cocci)
Spheric in shape, round-shaped, bean-shaped, oval-shaped, or even pointed variations
Characteristics of bacillus
Cylindrical, rod-shaped(blocky, spindled, long and threadlike, club-shaped, or round ended)
Characteristics of vibrio
A rod is gently curved
Characteristics of spirillum
slightly curled or spiral-shaped cylinder, rigid helix, corkscrew-like shape
Characteristics of spirochete
Containing periplasmic flagella, resembles a spring and are more flexible
Characteristics of branching filaments
produce many branches off a central rod structure
What are the divisions of cocci?
DIvision in one plane
Diplococcus(two cells), Streptococcus(coci in chains)
DIvision in two perpendicular planes
Tetrad(cocci of 4), Sarcina(pack of 8-64 cells)
Division in several planes
Staphylococci and micrococci(irregular clusters, varied cocci)
What are some appendages that can be present on prokaryotic cells?
Motility(flagella, axial filaments) or provide attachment/channels(fimbraie, pili, nanotubes/wires)
What are flagella used for?
Bacterial locomotion
What are the 4 flagellar arrangements?
Monotrichous, Lophotrichous, Amphitrichous, Peritrichous
