Microbiology Chapter 2 Flashcards
What are the nine different types of Prokaryotic bacterial morphologies
Cocci
Bacillus
Sprilla
Spirochetes
Filamentous
Streptococcus
Sarcina
Staphylococcus
Budding and appendaged
Cocci
Bacillus
Sprilla
Spirochetes
Filamentous
Streptococcus
Sarcina
Staphylococcus
Budding and appendages
Stalk & hypha
Explain why there are different bacterial morphologies and give examples
morphology is the result of selective forces that have shaped its evolution to maximize fitness. This can be in terms of nutrient uptake, gliding motility (filamentous), and swimming motility (sprilla)
What is the 2nd known biggest bacteria cell known? Does it have one or two genomes?
Epulopiscium fishelon, found in fish gut, it has many copies of genomes due to its large size.
What is the 1st known biggest bacteria cell? What is the theory for its large size?
Thiomargrita namibiensis, a sulfur-oxidizing chemolithotroph. It is a large cell for storing sulfur as an energy source
Are there any cell size rivals in Archaea?
No.
Large cells have a _________ ability to transport nutrients. Large cells have __________ metabolic rates. This means large cells are less ________ compared to smaller cells.
decreased, slow, competitive
Prokaryotes: S/V Ratio & its significance
Small cells have a higher S/V ratio
Small cells have a fast growth rate
A faster growth rate means a bigger population with more mutations meaning there are more evolutionary possibilities for Prokaryotes
S/V ratios control what two things
Growth rate and evolutionary possibilities
Eukaryotes: S/V Ratio & its significance
Large cells have a small S/V ratio
Mutation is masked 1/2 diploid cells
Slower growth rates mean a small population which means fewer mutations so there are fewer evolutionary possibilities for Eukaryotes
Cytoplasmic Membrance: Compare and Contrast Bacteria & Eukarya and Archaea
Bacteria & Eukarya:
Phospholipid bilayer, ester linkages bonding to fatty acids and glycerol, weak, and hopanoids
Archaea:
Lipid monolayer, ether linkages between glycerol and side chains, rigid, no hopanoids, isoprenes
What are the three functions of the Cytoplasmic Membrane?
Prevents leakage
Anchors proteins
Conserves energy
Is the cytoplasmic membrane impermeable or permeable? What does this mean?
Impermeable - transport proteins are needed.
What is the function of peptidoglycan? What are the two components of peptidoglycan?
Strengthens cell wall
N-acetyl glucosamine and N- acetylmuramic acid
What is the function of lysozyme? What does it affect?
Breaks the bond between N-acetylglucosamine and N-acetylmuramic acid thus weakening peptidoglycan and causing cell lysis. It also affects penciling by weakening the molecule and causing osmotic lysis.
Compare and Contrast Gram Positive and Gram Negative
Gram - positive: interbridges (glycines),
90% peptidoglycan
Gram-negative: small amount of peptidoglycan, the majority is composed of lipopolysaccharide (LPS)
Describe or draw the Cell Wall
Outer membrane: lipopolysaccharide (o specific polysaccharide, core polysaccharide, and Lipid A
Periplasm:
Porins vs Nonspecific Porins
Porins: allow the outer membrane to be permeable for small molecules. They are channels for entrance and exit.
Nonspecific porins: form water-filled channels for hydrophilic molecules to pass.
Describe the Archaea’s Cell Wall
Made up of pesudeomuerin; composed of N-acetylglucosamine and N-acetyltalosaminuronic acid.
Beta 1,3 instead of Beta 1,4
Immune to lysozyme and penicillin
Halococcus
stability of cell wall depends on the sodium sulfate complex; halophilic: salt-loving
The most common cell wall in Archaea?
S layers
What are the three functions of S layers
Allow passage of low molecular weight solutes
Retains protein near cell surfaces that function outside the cytoplasmic membrane and outer membrane
Retain periplasmic proteins and prevents drifting away in gram-negative bacteria
What can outer surface layers do?
Prevent dehydration, attachment (biofilms), virulence factors
Filamentous, allows cells to stick to surfaces. Form pellicles.
Fimbriae
Longer than Fimbriae, support twitching motility, facilitate gene exchange and enable adhesion of pathogens to host tissues.
Pilli
Twitching motility
Helps locate specific sites for attachement
Grappling hooks to help catch nutrients and not get washed away
Hamus
