functional anatomy of the prokaryotic cell Flashcards
what is the cell envelope
the plasma membrane and all layers external to it
what does glycocalyx mean
sugar coat
where is the glycocalyx
part of the cell envelope, exterior to the cell wall
what is the glycocalyx in terms of composition
a network of polysaccharides
what are the two types of glycocalyx
capsules and slime layers
when is the glycocalyx considered a capsule
when it is well organized and not easily washed off
when is the glycocalyx considered a slime layer
when it’s unorganized and loosely attached to the cell wall
what part of the cell is the glycocalyx attached to
the cell wall
where is the glycocalyx made
inside the cell
from being made inside the cell, how does the glycocalyx get outside of the cell
it’s secreted to the surface
T or F: all bacteria have a glycocalyx
false; not all of them do
T or F: for the bacteria that have a glycocalyx, the chemical structure is the same across species
false; the chemical structure will vary across species
describe the advantages of having a glycocalyx
they help bacteria resist phagocytosis b/c they’re slippery, they aid in attachment to surfaces, prevent desiccation b/c the layer contains lots of water, they inhibit entry to bacterial viruses or other hydrophobic toxic materials
what is the S layer
another layer of the envelope that may be present
what is the S layer attached to
the outermost portion of the cell wall
what does S stand for in S layer
surface
what is the S layer made up of
protein or glycoprotein
what are the functions of the S layer
protection against predacious bacteria/ion and pH fluctuations, or osmotic stress. Promotes adhesion to surfaces, helps maintain shape and rigidity, protects some pathogens against host defenses
T or F: bacteria can have both a glycocalyx and the S layer
true
T or F: all bacteria have a cell wall
true; except for a few instances
what are the major functions of the cell wall
protection against osmotic lysis, provides shape, protects against entry of toxic materials
is the cell wall external or internal to the glycocalyx and S layer
internal
what is the cell wall made up of
peptidoglycan
T or F: peptidoglycan is a polymer
true