Taller BIOL 3500 Homework
In archaeal membranes, what serves the same function as the fatty acids of bacterial membranes? glycerophosphates hopanoid molecules glycerol isoprene derivatives phosphate groups
isoprene derivatives
Starting from the inside of the outer membrane to the outside, what is the composition of lipopolysaccharide? O-specific polysaccharide, core polysaccharide, lipid A lipid A, O-specific polysaccharide, core polysaccharide O-specific polysaccharide, lipid A, core polysaccharide lipid A, core polysaccharide, O-specific polysaccharide
lipid A, core polysaccharide, O-specific polysaccharide
Scientists believe life may have begun as an RNA world because __________. RNA is essential to processes found in all cells RNA can bind small molecules RNA can have catalytic activity All of the listed responses are correct.
All of the listed responses are correct.
Which of the following are true regarding both flagella and pili? Select all that apply. Both flagella and pili are hollow inside. Both are extracellular surface appendages. Flagella and pili are made up of proteins Their functions include motility. Flagella and pili occur in both Bacteria and Archaea.
Both are extracellular surface appendages. Flagella and pili are made up of proteins Their functions include motility.
For early cells the major source of carbon was _________ and the major fuel for energy was __________ . CO2 ; H2 N2 ; H2 O2 ; CO2 CO2 ; N2
CO2 ; H2
Which of the following are true of capsules? Select all that apply. Capsules retain water and help prevent desiccation of the bacteria. Capsules are considered part of the cell wall. Capsules are involved in the attachment of microorganisms to solid surfaces. Capsules occur in both Bacteria and Archaea. Capsules help hide bacterial cells from the host immune system
Capsules retain water and help prevent desiccation of the bacteria. Capsules are involved in the attachment of microorganisms to solid surfaces. Capsules occur in both Bacteria and Archaea. Capsules help hide bacterial cells from the host immune system.
Which is a function of the cytoplasmic membrane in prokaryotes? It is a major site of energy conservation. It is an anchor for many proteins involved in bioenergetic reactions and transport. It functions as a permeability barrier. Membranes have all of the above functions.
Membranes have all of the above functions.
The lipids in the cytoplasmic membrane of Bacteria and ________ contain ester linkages, while the cytoplasmic membrane of ________ contain ether linkages. Archaea / fungi Eukarya / prokaryotes Archaea / Eukarya Eukarya / Archaea
Eukarya / Archaea
Porins are present in ______________bacteria because, in these organisms, molecules entering the cell must pass through an extra layer of ___________. Gram-positive; peptidoglycan Gram-negative; peptidoglycan Gram-negative; membrane Gram-positive; membrane both Gram-negative and Gram-positive; membrane
Gram-negative; membrane
Which statement best illustrates the importance of a high surface-to-volume ratio that is found in microorganisms? If a cell has a high surface-to-volume ratio, there will NOT be enough surface area to get the needed nutrients in to support cellular metabolism and the accumulated waste out. If a cell has a high surface-to-volume ratio, the volume of the cell will be much larger than the surface area. There would NOT be enough surface area to get the needed nutrients in and the accumulated waste out. If a cell has a high surface-to-volume ratio, the volume of the cell will be much larger than the surface area. There would be enough surface area to get the needed nutrients in and the accumulated waste out. If a cell has a high surface-to-volume ratio, there will be enough surface area to get the needed nutrients in to support cellular metabolism and the accumulated waste out.
If a cell has a high surface-to-volume ratio, the volume of the cell will be much larger than the surface area. There would be enough surface area to get the needed nutrients in and the accumulated waste out.
Endotoxin is a protein secreted by certain pathogenic Bacteria. a toxin produced within archaeal cells. LPS released from gram-negative outer membranes. a toxin produced in the periplasm of most bacteria. a toxin known for its primary attack on the epidermis of mammals.
LPS released from gram-negative outer membranes.
Which of the following molecules is shared by both Gram-positive and Gram-negative organisms? lipid A lipopolysaccharide endotoxin N-acetylmuramic acid lipoteichoic acid
N-acetylmuramic acid
If photosynthetic organisms were present when the earth was primarily anoxic, why was the development of cyanobacteria critical for the oxidation of the atmosphere? Cyanobacteria carry out anoxic photosynthesis. The early forms of photosynthesis did produce oxygen, but it was not enough to make a difference in the atmosphere. The early forms of photosynthesis did not produce oxygen as a waste product. The early forms of photosynthesis were carried out in the water and there was no way for the oxygen to move into the atmosphere.
The early forms of photosynthesis did not produce oxygen as a waste product.
If two prokaryotes were going to be considered as the same species, what criteria would apply? (Check all that apply) The two microbes have >96% average nucleotide identity (ANI) The two microbes must be found colonizing the same environment. The two microbes have >98.6% 16S rRNA gene sequence identity. The two microbes have phenotypic similarity. The two microbes must be grown in pure culture.
The two microbes have >96% average nucleotide identity (ANI) The two microbes have >98.6% 16S rRNA gene sequence identity. The two microbes have phenotypic similarity.
Check all the reasons why a microbial species is difficult to define. Microbes are very difficult to sequence. There is a very limited fossil record for microbes. Microbes have limited morphological features. Microbes don't use sexual reproduction. Molecular techniques don't work on microbes.
There is a very limited fossil record for microbes. Microbes have limited morphological features. Microbes don't use sexual reproduction.
Which of the following is LEAST commonly associated with endospore-forming bacteria? They can survive adverse environmental conditions. They are primarily soil dwellers. They are coccus-shaped organisms. They are saprophytic.
They are coccus-shaped organisms.
One type of archaeon, Haloquadratum walsbyi, is shaped like a postage stamp with dimensions of 2 µm x 3 µm x 0.25 µm. What likely advantage would this shape provide? This shape increases the surface to volume ratio enabling more efficient nutrient uptake. This shape is more conducive to the formation of biofilm communities. This shape enables this bacteria to float on surfaces and obtain better light exposure. This shape is difficult for phagocytic cells to attach to and engulf.
This shape increases the surface to volume ratio enabling more efficient nutrient uptake.
Type IV pili are involved in twitching motility and attachment of cells to surfaces. attachment of cells to surfaces. attachment to surfaces, twitching motility, and pathogenesis. twitching motility. pathogenesis.
attachment to surfaces, twitching motility, and pathogenesis.
The main functions of the bacterial cell wall include all of the following EXCEPT __________. limiting cell size actively transporting solutes against the concentration gradient resisting cell lysis due to osmotic forces conferring a specific shape to the cell
actively transporting solutes against the concentration gradient
Arrange the types of microorganism in the order they evolved on Earth. anaerobes, anoxygenic phototrophs, oxygenic phototrophs, aerobes, multicellular organisms anaerobes, multicellular organisms, aerobes aerobes, oxygenic phototrophs, anoxygenic phototrophs, anaerobes, multicellular organisms anaerobes, anoxygenic phototrophs, aerobes, oxygenic phototrophs, multicellular organisms
anaerobes, anoxygenic phototrophs, oxygenic phototrophs, aerobes, multicellular organisms
Archaea with a plasma membrane composed of diglycerol tetraethers would most likely be found ______. in the soil at a temperature of 90oC in a constantly cold environment at a pH of 2 in the mammalian gut
at a temperature of 90oC
Prokaryotic cells often have inclusions in their cytoplasm. Inclusions are used in all of the following EXCEPT attachment to surfaces nutrient storage orienting in the magnetic field buoyancy in the water column organizing metabolic functions such as fixation of carbon dioxide
attachment to surfaces
The enzyme lysozyme kills bacterial cells by cleaving the beta 1,4-glycosidic bonds in the peptidoglycan. This leads to which of the following? the inability of the cell to grow and divide breaches of the cell wall and cell lysis due to osmotic swelling lysis of the cell due to the same mechanism used by penicillin out of control cell growth
breaches of the cell wall and cell lysis due to osmotic swelling
Microorganisms play key roles in the cycling of important nutrients in plant nutrition, particularly those of carbon and nitrogen nitrogen. carbon, nitrogen, sulfur, and phosphorus. carbon. sulfur.
carbon, nitrogen, sulfur, and phosphorus.
A major function of prokaryotic gas vesicles is to keep the cell's organelles separated during flagellar motion. store oxygen for aerobic growth when oxygen becomes depleted in the environment. confer buoyancy on cells by decreasing their density. serve as a reservoir for oxygen and carbon dioxide.
confer buoyancy on cells by decreasing their density.
What molecules reduce the water content of a bacterial endospore? small acid-soluble proteins and dipicolinic acid diaminopimelic acid and calcium peptidoglycan and calcium dipicolinic acid and calcium small acid-soluble and core proteins
dipicolinic acid and calcium
Endospores represent a challenge to the fields of industrial and medical microbiology because endospore-forming organisms are often dangerous pathogens. endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, and endospore-forming organisms are often dangerous pathogens. they are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive. endospores are significantly smaller than vegetative cells. endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, endospore-forming organisms are often dangerous pathogens, and endospores are significantly smaller than vegetative cells.
endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, and endospore-forming organisms are often dangerous pathogens.
Predict which type of organism would be more difficult to treat with antibiotics and why. gram-positive organisms -- thicker peptidoglycan layer gram-negative organisms - outer membrane gram-negative organisms -- periplasm gram-positive organisms - lipoteichoic acid
gram-negative organisms - outer membrane
When you see a publication describing an enzyme from Candidatus Pseudomonas utahensis you can infer that this organism (select all that apply) is described in Bergey's Manual of Systematic Bacteriology. has been deposited in a culture collection. has been grown in pure culture.has not been grown in pure culture. has not been formally recognized as a species.
has not been grown in pure culture. has not been formally recognized as a species.
Compared to Eukaryotes, Bacteria and Archaea have ________ surface-to-volume ratios, causing ________ nutrient exchange and growth rates. lower / higher higher / lower higher / higher lower / lower
higher / higher
Most prokaryotic cells reside on Earth's surface. in and on nonprokaryotic organisms (including humans and other animals). in the oceanic and terrestrial subsurfaces.in lakes, rivers, and oceans.
in the oceanic and terrestrial subsurfaces.
Which of the following regarding microcompartments is false? Microcompartments include carboxysomes consist of a virion-like protein shell encapsulating enzymes. are to bacteria what membrane-bound organelles are to eukaryotic cells. include gas vesicles
include gas vesicles
Like all forms of life on Earth, all microbial cells perform three major types of activities: __________. metabolism, growth, and evolution growth, genetic exchange, and evolution growth, differentiation, and metabolism metabolism, growth, and genetic exchange
metabolism, growth, and evolution
The largest mass of living material on Earth comes from plants. microorganisms. plants and animals together. animals.
microorganisms
You have discovered a new coccoid-shaped microorganism with no nucleus, a rigid cell wall, and a diameter of 2 µm. Chemical tests reveal that its cell wall does NOT contain peptidoglycan. The new microorganism is most likely a eukaryote. most likely an archaeon. most likely a bacterium. either a bacterium or an archaeon.
most likely an archaeon.
Metagenomics involves the analysis of a microbial community by __________. generating a complete sequence of the genomes of all of the organisms in an environment sampling and sequencing all of the genes in an environment generating a phylogenetic tree based on all of the versions of a gene in an environment sequencing all of the community RNA in an environment
sampling and sequencing all of the genes in an environment
Eukaryotes have ________ in their cytoplasmic membranes, which serve to strengthen and stabilize the membrane and make it less flexible. Many bacteria have similar molecules, known as ________, in their cytoplasmic membranes that have a similar role. sterols / hopanoids phospholipids / lipopolysaccharides ether bonds / ester bonds lipids / phospholipids
sterols / hopanoids
All the following are prokaryotic storage polymers EXCEPT glycogen magnetite sulfur polyphosphate polyhydroxyalkanoate
sulfur
What was LUCA? the last organism prior to the divergence of bacteria and archaea the first cellular organism to evolve the type of prokaryote that evolved into a eukaryote the last eukaryote before eukaryotes diversified
the last organism prior to the divergence of bacteria and archaea
Mycoplasma species are bacteria that do not possess a cell wall. What accounts for the extra strength and rigidity of a mycoplasmal cell membrane? the presence of hopanoids in their membranes the presence of LPS in their membranes the near absence of proteins in their membranes the presence of sterols in their membranes the presence of ether-linked lipids in their membranes.
the presence of sterols in their membranes