Microbial Cell Structure and Function Flashcards
Bacterial habitats
Terrestrial and aquatic
How do bacteria reproduce? What is the term for this type of reproduction?
Reproduce asexually, called binary fission
Size range of bacteria
0.3-100 micrometers
Average size of bacteria (E. coli cell)
4 micrometers
Thiomargarita size
Greater than 100 micrometers
Coccus
Spherical shape
Diplococcus
Pairs of cocci (spheres)
Streptococcus
Chains of cocci (spheres)
Staphylococcus
Grape-like clusters of cocci (spheres)
Tetrads
4 cocci in square
Bacillus
Rod shape
Vibrio
Curved rod shape (crescent moon or comma)
Spirillum
Rigid helical shape
Spirochete
Flexible helical shape
Pleomorphic
Variable shape
Hyphae
Long filaments formed by some bacteria and many fungi
Mycelium
Network of hyphae
Deinococcus genus
Form tetrad shape
Radiation resistant
Mycoplasma genus
Form pleomorphic shape
Plasma membrane, but no cell wall
Shape of E. coli
Bacillus
Surface to volume ratio and size of cells
Smaller cells, higher surface to volume ratio
Advantages to small size of bacteria
More efficient nutrient uptake
Faster growth
Cell envelope: 3 components
Plasma membrane
Cell wall
Layers outside cell wall
Plasma membrane encompasses what?
Cytoplasm
Selectively permeable membrane
Plasma membrane is selectively permeable
Makes sure that only necessary compounds are brought into cell
Main site of energy generation in bacterial cell
Plasma membrane
What structure enables energy generation in plasma membrane?
Electron transport chains
Function of transport systems in bacterial cell
Bring nutrients into cell
Function of signal transduction systems in plasma membrane
Sense and respond to environment
Components of fluid mosaic model of plasma membrane
Lipid bilayers (polar heads and nonpolar tails) Floating proteins
Lipids of bilayer have what type of bonds?
Flexible ester bonds
Term for molecules having both polar and nonpolar components
Amphipathic
Type of molecules that stabilize plasma membranes of eukaryotes
Sterols
Type of molecules that stabilize plasma membranes of bacterial cells
Hopanoids (similar to sterols)
Hopanoids are found in what fuel source?
Petroleum