Download Plasma membrane acts as a selective barrier allowing nutrients to

1. Plasma membrane acts as a selective barrier
allowing nutrients to enter the cell and wastes to
leave the cell.
2. Peptidoglycan is the MOST common compound in
the cell walls of gram-positive bacteria.
3. Gram-positive bacteria should be very vulnerable
to inhibition by penicillin because penicillin is an
antibiotic that inhibits enzymes from catalyzing the
synthesis of peptidoglycan.
4. Bacteria rarely thrive in high sugar content foods,
even if the food containers are left open, because
the bacteria undergo death by plasmolysis.
5. Correct order of how a predatory bacterium such
as Bdellovibrio bacteriophorus may drill into its
prey’s cytoplasm.
 Capsule
 Membrane composed of lipopolysaccharides
 Peptidoglycan
 Membrane composed of phospholipids
6. If a bacterium possesses antibiotic resistance and
the potential to persist through very adverse
conditions such as freezing temperatures, where
should the DNA be located? The nucleoid region,
endospore, and/or plasmids.
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7. A complex “motor” is embedded in the cell wall
and plasma membrane of the typical prokaryotic
flagellum.
8. The prokaryotic chromosome is not contained
within a nucleus, but, rather is found at the
nucleoid region.
9. The following statements are in relation to a grampositive prokaryotic cell.
 The cell wall is composed almost entirely of
peptidoglycan.
 Flagellum requires ATP to function, and
permits some species to respond to taxes.
 A capsule is not present in all bacteria, this cell
covering enables cells that possess it to resist the
defenses of host organisms.
 The endospore is not present in all bacteria.
This structure enables those that possess it to
germinate after exposure to hard conditions.
 The sex pilus is a structure that permits
conjugation.
10.
The cell wall is an important source of
endotoxins in gram-negative species.
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11.
Mutation is a primary source of variation I
prokaryote populations.
12.
Prokaryotes divide by binary fission, without
mitosis or meiosis.
13.
Bacteria can grow and genetically change
quickly; this can be graphed. A period of time
depicting a high rate of genetic change may have a
steep slope on a line graph.
14.
To increase the number of bacteria, and thus
genetic variation through possible beneficial
mutations, binary fission must take place.
15.
Chemotroph: an organism that obtains its
energy from chemicals.
16.
Heterotroph & Chemotroph: A prokaryote
that obtains both energy and carbon as it
decomposes dead organisms. Both can also obtain
carbon and energy by ingesting prey.
17.
Parasitic chemoheterotrophs are responsible
for many human diseases.
18.
Cyanobacteria are examples of
photoautotrophs.
19.
Photoautotrophs use light energy to synthesize
organic compounds from CO2.
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20.
Chemoautotrophs obtain energy by oxidizing
inorganic substances; energy that is used, in part,
to fix CO2.
21.
Photoheterotrophs use light energy to generate
ATP, but they do not release oxygen.
22.
Photoautotrophs are responsible for high
levels of O2 in the atmosphere.
23.
How do animals gain access to fixed nitrogen if
no nitrogen-fixing prokaryotes are known to live
inside animals?
 They may ingest nitrogen fixers.
 They may ingest plants that harbor nitrogen
fixers.
 They may ingest other animals that ingest
nitrogen fixers or plants with nitrogen fixers.
24.
The genomes of archaeans may be unique;
nonetheless, they do contain genes that originated
within bacteria and have since adapted to unique
environments.
25.
Both archaeans and bacteria have plasma
membranes and both lack nuclear envelopes. They
may or may not have the same cell wall or have
identical rRNA sequences.
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26.
Extreme halophiles should be expected to be
most strongly resistant to plasmolysis in hypertonic
environments.
27.
Sulfolobus acidocaldarius is a
thermoacidophile that lacks peptidoglycan. What
can we concur from this information?
 It is an archaean.
 The optimal pH of its enzymes will below pH7.
 It could inhabit hydrothermal springs.
28.
The primary ecological role of prokaryotes is
to break down organic matter.
29.
The recycling of nutrients would be greatly
reduced, at least initially, if all prokaryotes on
Earth suddeny vanished.
30.
A bacterium lives on a leaf. The bacterium
eats the leaf’s waxy coating but inhibits the growth
of other microbes on that leaf. The bacterium can
cause a fatal disease if it enters the inside of the
leaf. When the plant dies, the bacterium and its
offspring decompose the plant. What roles do the
bacterium play?
 The bacterium is a mutualist, a parasite, and a
nutrient recycler.
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31.
Why can prokaryotes be considered more
successful on Earth than humans?
 More numerous.
 More biomass.
 More diverse in metabolism.
 Can occupy more diverse habitats.
32.
Closing previously opened containers is not a
good way to slow down or prevent bacterial growth
in comparison to refrigeration, pickling,
irradiation, or using lots of sugar.
33.
Overusing antibiotics can encourage the
growth of more antibiotic-resistant strains of
bacteria.
34.
Broad-spectrum antibiotics can inhibit the
growth of healthy intestinal bacteria and can thus
cause a patient to become deficient in certain
vitamins.
35.
Genetic variation in bacterial populations can
result from transformation, mutations,
conjugation, and transduction, but not from
meiosis.
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