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prepare 2.1

Terms in this set (28)

What are the two types of bacterial movement?
nonflagellar and flagella motility
Nonflagellar motility involves what?
flagella independent motility
nonflagellar motility is what in comparison to swimming?
slower and smoother
With nonflagellar motility movement typically occurs along what?
long axis of cell
What are examples of nonflagellar motility?
gliding and twitching motility
Gliding motility
smooth sliding over a surface, not very well understood
twitching motility
extension and retraction of type IV (4) pili; relatively slow and very jerky
Which is the better method to move: nonflagellar or flagella motility
flagella motility
Flagella motility
flagella increase or decrease rational speed in relation to strength of the proton motive force
How does flagella motility move?
rotate clockwise or counterclockwise
Other cell surface structures
- S layer
- capsules
- fimbriae
- pilus
- flagella
- endospores
What are the 3 parts that flagella are composed of?
1. filament
2. hook
3. basal body
filament
made up of flagellin proteins
hook
protein portion that connects filaments to basal body
basal body
disk-like structure that produces torque on filament to turn it like a propeller (embedded within cell envelope)
Bacterial flagella are driven how?
proton motive force
Flagella spinning counterclockwise produce a __________ directional movement
"run"
Flagella spinning clockwise produces a ______ movement
"tumble" (random movement)
Endospores main focus is to do what?
protect DNA
Endospores form through a process called?
sporulation
What is sporulation?
when cell growth stops due to harsh conditions
Sporulation and endospores form within and at the expense of the ______________.
vegetative cells (high vegetative activity)
Endospores are highly differentiated cells resistant to
heat, harsh chemicals and radiation
How long can endospores survive?
indefinitely
Endospores are only present in some gram-positive bacteria
E.g. Bacillus and Clostridium
Endospores contain dipicolinic acid and a lot of ____________
Ca+
Complex of calcium-dipicolinic acid helps to stabilize ___________.
DNA and protect it from heat denaturation
When does germination occur?
when the environment becomes favorable again, germination occurs
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