Chapter 3: Prokaryotic Cells Flashcards
Prokaryotes
unicelluarl; lack a membrane bound nucleus; lack membrane bound organelles
Monomorphic Bacteria
have one shape
Pleomorphic Bacteria
can take on different shapes/forms; this enhances their survival and appears to be important for transmission to a new human host
Prokaryote Sizes
rang from 0.2-750 micrometers in diameter; but average 0.5-2.0; mycoplasma species are some of the smallest; thiomargarita magnifica are some of the largest
Why are prokaryotes small?
surface area to volume ratio; they use diffision and a small size gives them a larger surface area voume ratio
Bacilli
singular: bacillus; rod shaped
Cocci
singular: coccus; spherical shape
Vibrio
comma shaped
Stella
star shaped
Coccobacilli
ovoid
Spirochetes
spiral shaped, corkscrew motion
Diplococci
paired cocci
Streptococci
chains of cocci
Staphylococci
grapelike clusters
Diplobacilli
paired bacili
Streptobacilli
chains of bacilli
Palisade
clusters of bacilli
Binary Fission
how prokaryotic cells reproduce; form of asexual reprduction which produces two “daughter” cloned cells
Steps of Binary Fission
DNA is copied; cell grows; copied chromosome is drawn to opposite ends of the cell’ septum (partition) begins to form at the midpoint;septum eventually walls off the resulting two daughter cells from one another
Extracellular structures
structures outside of the plasma membrane
Intracellular Structures
structures that lie within the boundary defined by the plasma membrane
Plasma Membrane
thin, flexible, phospholipid bilayer; selective barrier; proteins can constitue half of the plasma membrane mass; also a site for metabolic reactions (ETC) to make ATP
Selective Permeability
gases, water and small (nonchargged)substances can diffuse in and out of the cell; ions and larger polar substances require protein transporters to enter or exit a cell
Factors that Affect Fluidity of Plasma Membrane
temp (warm increase fluidity and cold reduce fluidity); fatty acid content (unsaturated fatty acid improve fluidity; saturated fatty acids are more rigid in cold)
Bacterial Plasma Membrane
linear fatty acids
Archeal Plasma Membranes
long branched fatty acids; certain archaea that live in extreme heat build lipid monolayers as opposed to lipid bilayers
Cell Wall of Bacteria
peptidoglycan as a core component of their cell walls; interchanging NAM and NAG that create a mesh like structure; LETS ANY thing thorugh NOT semipermeable
Cell Wall of Archeae
Pseudopeptidoglycan is core component
Gram Negative Bacteria Cell Wall
thin peptidoglycan layer; periplasmic space; outermembrane; contains lipopolysaccharid LPS; stain pink
Gram Positive Bacteria Cell Wall
thick peptidoglycan layer; lack an outer membrane; stain purple