Ch 7 Bacterial Cell Structure/Function II Flashcards
What does RNA polymerase do?
Transcribes DNA into a single strand of RNA
The main structural difference between eukaryotic cells and prokaryotic cells
Eukaryotes have a well-defined nucleus
Prokaryotes have a nucleoid region
What does mRNA do?
It binds to a ribosome for translation into a polypeptide
What does a tRNA do?
Aids mRNA by bringing the amino acids to the ribosome
True or False: Prokaryotes transcription and translation is very separate
False, they are tightly coupled
What is a signal recognition particle (SRP)?
Binds to growing peptides to help in protein synthesis
How does Bacterial DNA replicate
In coordination with cell expansion producing two daughter cells
What is the ori site?
The origin
True or False: DNA replicates bidirectionally
True
How does DNA replicate bidirectionally?
There are two replication forks where DNA is synthesized by DNA polymerase and accessory proteins until the termination site is made, then the replication forks separate from the DNA
What does the generation of the termination site do?
Triggers growth of the septum which eventually separates in to two daughter cells
Septation: Which bacteria is associated with parallel planes?
Streptococci
Septation: Which bacteria is associated with random planes?
Staphylococci
Septation: Which bacteria/yeast is associated with perpendicular planes?
Tetrad and Sarcina
What is asymmetrical cell division?
One daughter cell is stationary while the other is motile
What are thylakoids?
Extensively fold intracellular membranes that contain chlorophyl
What are carboxysomes?
Have the enzyme Rubisco for CO2 fixation
What are gas vesicles used for ?
Increased buoyancy
What do storage granules…store?
Glycogen, PHB, PHA, (for energy)
Sulfur (for oxidation)
What are magnetosomes?
Membrane-embedded crystals of magnetite, Fe3O4 (swimming)
What are pili used for?
Attachment
What is another name for pili?
Fimbriae
What are sex pili used for?
Conjugation
What are stalks?
Membrane-embedded extensions of the cytoplasm that secrete enzymes called holdfasts (adhesion)
What are nanotubes?
Intercellular connections that pass material from one cell to another
Who uses rotary flagella?
Motile prokaryotes
What do the rotary flagella look like on peritrichous cells?
Randomly distributed around the cell
What do the rotary flagella look like on lophotrichous cells?
They are at the end of the cell
What do the rotary flagella look like on monotrichous cells?
They only have one
True or False: Flagellin is driven by a Sodium-Potassium pump
False: proton motive force
What is chemotaxis?
The movement of bacterium in response to chemical gradients
When do bacteria (by flagellum) move CCW?
With attractants (run)
When do bacteria (by flagellum) move CW?
With repellants (tumble)
True or False: Environmental stress can cause bacteria to change cell structure
True
What is sporulation?
Process executed to adapt to starvation, forming an endospore which is dormant
What are heterocysts?
Cyanobacteria form these when oxygen is low and are still able to maintain oxygenic photosynthesis
What are fruiting bodies?
When starved they swarm together when they sense food
What are filamentous structures?
The hyphae from fungi separate into arthrospores when starved to prevent drying out
