Unit 4 Flashcards
Carbohydrates
- largest / diverse
- energy source
- important for cell biological function
What type of macromolecules are sugar/starches
carbohydrates
Monosaccharides , polysaccharides , disaccharides
carbohydrates
Lipids
- for structure/ cellular membrane
- holds cell together / can collapse without it
- fats
Proteins
- cell structure/ function
- Oxygen Nitrogen Hydrogen
Nucleic acids
- Replication , transcription , translation
Flagella (prokaryotes)
- provide motility/ locomotion
- attach to basal body
- do not move in directional format
Photosynthetic prokaryotes
- will move in directional format due to specialized receptors
Atrichous
No flagella
Do all cocci lack flagella?
true
The 4 types of flagellum
Monotrichous
Amphitrichous
Lophotrichous
Peritrichous
Monotrichous
one flagella at one pool
Amphitrichous
flagella at both pools of a cell
Lophotrichous
flagella clumped at one end of pool
Peritrichous
flagella distributed over entire cell
What protein is flagella composed of?
flagellin
Flagellin protein H antigen
used to distinguish sub species
What does the basal body do for flagella
anchors flagella to the cell wall and cell membrane
Axial filaments
- found on spirochete bacteria (spiral shape)
- anchored at one end and wrapped around cell
-corkscrew motion
Spirochetes
allow bacteria to move as it contracts/ expands
Pili (pilus) or Fimbrae (fimbria)
- many gram neg have pili
What is the purpose of pili
- to adhere to surfaces (colonization)
- conjugation (transfer DNA)
Cell wall purpose
- structure/shape
- provides shape
-protects cell membrane - anchors flagella -> basal body
- prevents rupture of cell in hypotonic solutions
Composition of cell wall
PG or peptidoglycan also known as meurin
- found in more gram+
What is PG composed of
- NAG (N acetyl glucosamine)
-NAM (N acetyl muramic acid) - Tetrapeptide side chain attached to NAM in backbone
- Peptide cross bridge that links tetrapeptide sidechain
NAG/NAM
carbohydrate layer of PG
Gram - cell wall
- thin layer of PG
-Lipid bilayer (composed of lipids)
What does mycoplasma sp. lack
cell wall
Outer membrane (lipid layer of gram - cel wall)
lipid layer acts as a barrier against enzymes detergents and antibiotics
Periplasmic space
- thin layer of PG which is susceptible to mechanical breakage
Cell membrane in prokaryotes (cytoplasmic or plasma membrane)
- composed of phospholipid bilayers
- less rigid than cm in eukaryotes
- no sterols
Function of cell membrane in prokaryotes
-ATP synthesis
- selective permeability
- photosynthesis in some bacteria
What is the polar hair of the cell membrane
hydrophillic
What is the non polar hair of the cell membrane
hydrophobic
Cytoplasm (in prokaryotes)
substance of cell inside cell membrane
- 80% h20, proteins, carbohydrates, lipids, in organic ions
Where does all activity happen in prokaryote cells
within cell membrane of the cell
Nucleoid (prokaryotes)
- nuclear area
- circular double stranded DNA
-bacterial chromosome
-No nucelar membrane or histone proteins like eukaryotes
Where does the nucleoid attach to
cell membrane
Plasmids (prokaryotes)
-optional in prokaryotes
-small circular double stranded DNA
- not connected to bacterial chromosome
-extra chromosomes for bacteria
- plasmids can replace their own
- can be gained or lost with no harm to bacterial cell
Ribosomes (prokaryotes)
- protein synthesis
- several antibiotics inhibit the bacterial ribosome from synthesizing proteins
Inclusions (prokaryotes)
- reserve deposits
- holds glycogens/lipids
- important for ATP synthesis
- metachromatic granules contain phosphate for ATP
Endospores (prokaryotes)
-protects cell from adverse environmental condition
-surrounds newly replicated DNA
Sporulation
process that endospore is being formed within vegetative state
Germination
Can go back to vegetative state
When happens when endospores mature
cell ruptures and endospores are free
Location of endospores
terminal
subterminal
central
What is the spore coat of endospores consist of
Ca++
PG
Dipicolinic acid
Capsule (prokaryotes)
-Glycocalyx or sugar coat
-external to cell wall
- provides cell with the ability to resist host defenses (phagocytosis) / lysozymes)
-stained with india pink
- virulent
Composition of capsules
mucopolysachhaides
Examples of capsules
pasteurella multocida
S. pneuomnaie
H. Influenzae
Examples of endospores
Clostridium sp.
Bacillus sp.
Cocci (coccus)
- round cells
-atrichous (no flagella)
Diplococci
cocci next to each other
Streptococci
cocci in chain
Tetrad
groups of 4 cocci
Sarcinae
groups of 6 cocci
Staphlycocci
cluster of cocci together
Bacilli (bacillus)
- some motile some cant
- rod shaped
3 types of spiral bacteria
- vibrio
- spirillium
- spirochetes
Vibrio
curve spiral bacteria
Spirillium
rigid spiral bacteria
Spirochetes
- flexible spiral bacteria
-corkscrew
3 shapes of bacteria
- cocci
-bacilli
-spirals
Psychrophiles
- cold loving
-optimum temp = 15 degrees celsius
Mesophiles
- loves moderate temp
- optimum temp = 25-40 degrees
-most common; very adaptive - most common cause of food spoilage/ disease causing
Thermophiles
- heating loving
- optimum temp = 50-60 degrees
-sunlit area/ hot springs
What grows in pH of 6.5 -> 7.5
bacteria
What grows in pH of 5 -> 6
molds (more acidic)
Osmotic pressure
force which a solvent moves across a semi-permeable membrane (cw/cm) from a solution of low concentration -> solution of higher solute concentration
Agar
-solidifying agent
- no benefits
Na agar
has proteins
PDA agar
has carbohydrates
3 types of osmotic pressures
-isotonic
-hypotonic
-hypertonic
Isotonic
- no movement of water in/out cell
- equal inside / outside of cell
Hypertonic
- water leaves the cell
- more solute than solvent
-cw/ cm pull apart
-plasmolysis / bacteriostatic occurs - used for food preservation
Hypotonic
- water enters the cell
- less solute / more solvent
- cell swells/ bursts
-occurs in gram -
plasmolysis
- shrinkage of cell’s cytoplasm
bacteriostatic
- cell growth is inhibited
what is used for preservation in hypertonic solution
salt brines/ sugar syrups
Osmophiles
likes hypertonic conditions
Halophiles
salt loving
- found in oceans/ salt mines
Saccharophiles
- sugar loving
- found in compost piles / grain silos
Autotrophs
self feeders
carbon source = carbon
Photoautotroph
Energy is from light
Cyanobacteria is an example of what
photosynthetic bacteria
Chemoautotrophs
energy from inorganic compounds
Heterotrophs
carbon source is organic compounds
feed on others
Photoheterotrophs
energy = light
- ex: green non sulfur/ purple non sulfur
Chemoheterorophs
energy / carbon source = organic compounds
most bacteria / fungi / protozoa / animals
Saprophytes ( feed on dead organic molecules) and parasites are examples of what?
chemoheterotrophs
Strict aerobe
-requires oxygen
-oxygen = final electron acceptor
- goes through cellular respiration
Cellular respiration stages
- glycolysis (2 atp’s)
- kreb’s cycle (2 atp’s)
- electron transport chain (34 atp’s)
How many atps does bacteria create
38
how many atps do eukaryotes create?
36
where is glucose in bacteria located during atp synthesis
cell membrane
where is glucose in eukaryotes located during atp synthesis
mitochondria
strict aerobe
growth at top of the tube
strictly needs oxygen
Pseudomonas sp. is an example of what type of aerobe
strict aerobe
strict anaerobe
- no oxygen
- organic compounds = final electron acceptor
- goes through kreb’s cycle -> fermentation process
what are the 2 final pathways for strict anaerobes
- anaerobic respiration (less than 38 atps )
- fermentation
Fermentation
goes through glycolysis only but then makes an end-product
ethanol , lactic acid, sulfur are examples of what during fermentation
end products in fermentation
Clostridium sp. is an example of what kind of anaerobe
strict anaerobe
Where does strict anaerobe grow in broth tube
at the bottom of tube away from the oxygen
Facultative aerobe/ anaerobe
- can live in the presence or abscence of oxygen
- growth throughout the tube
E. coli is an example of what
facultative bacteria
Microaerophilic
- tolerate small amount of oxygen
- growth is in the middle
Neiserria gonorrhoeae is an example of what
microaerophillic
what is required in a culture media
proper food elements , temp, oxygen available or not , moisture , pH , and sterile
where is agar derived from
algae / marine seaweed
Binary fission
generation time or doubling time
Binary fission equation
t = 2^n * the number of cells
the 4 stages of the bacterial growth curve
1) lag phase
2) log phase
3) stationary phase
4) death phase
lag phase
no bacterial growth / preparing for population growth
log phase
exponential growth / where binarry fission occurs (more dna replicate)
stationary phase
equilibrium of bacteria
Death phase
population decreases
Genetic recombination
- transfer of genetic information
- exchange of genes between 2 DNA molecules to form new combinations of genes on a chromosome
what are the 3 methods of genetic recombination
1) transformation
2) conjugation
3) transduction
transformation
- take plasmid (piece of DNA) and inserts into plasma or cell wall
- transfer of plasmid from donor cell -> recipient cell
Plasmids in transformation
- linear or circular
- can exist inside / outside of cell
- enters through pores of cell wall/ cell membrane
are the donor / recipient cell the same species
true
conjugation
- cell to cell contact
- opposite mating strains and pili
pili purpose during conjugation
used for contact -> contact
2 types of cells in during conjugation
F+
F-
F+ cell in conjugation
has pili and plasmids
the donor cell
F- cell in conjugation
no pili or plasmids (reciepient)
HFR ( high frequency of recombination)
plasmid becomes integrated into bacterial chromosome
Transduction
- virus or bacteriophage os involved
- virus attaches to bacterial cell
- virus acts as a vector by transporting bacterial DNA from donor cell -> recipient cell
- virus only attack bacteria
- DNA of phase virus integrates into bacteria’s chromosomes
Capsid
protective mechanism for virus
dna is inside capsid
