Chapter 20 FULL
Prokaryotes are now divided into the A. archaea and bacteria. B. bacteria and cyanobacteria. C. photosynthetic bacteria and chemosynthetic bacteria. D. archaea and cyanobacteria. E. autotrophs and heterotrophs.
A. archaea and bacteria.
Chemoautotrophs oxidize which of the following to obtain the energy necessary to reduce carbon dioxide to an organic compound? hydrogen gas hydrogen sulfide ammonia All of the above choices are correct. hydrogen sulfide and ammonia only.
All of the above choices are correct.
Which of the following could be used to grow lysogenic viruses in the laboratory? chicken eggs cell culture bacteria All of the choices could be used.
All of the choices could be used.
Which enzyme enables a retrovirus to convert its' RNA genome into DNA? A. DNA helicase B. reverse transcriptase C. DNA ligase D. reverse helicase
B
Ivanowsky first recognized that something smaller than a bacterium, called a filterable virus, was able to cause disease in the year A. 1965. B. 2001. C. 1892. D. 1700. E. 1650.
C. 1892.
Decomposers
Chemoheterotrophic prokaryotes function as decomposers. They break down dead things and unlock supplies of carbon nitrogen and other elements.
Viruses are categorized according to all of the following EXCEPT A. size and shape B. their type of nucleic acid C. the presence of absence of an envelope D. their method of reproduction, whether asexual or sexual
D
Which description best describes the cell wall of a Gram-positive bacteria? A. it is composed of a single plasma membrane and a thin outer layer of peptidoglycan B. it is composed of a double layer in the plasma membrane and a thin outer layer of peptidoglycan C. it is composed of a double layer in the plasma membrane and a thick outer layer of peptidoglycan D. it is composed of a single plasma membrane and a thick outer layer of peptidoglycan E. it is composed of single plasma membrane and a thin outer layer of cellulose
D
All of the following are true of methanogens EXCEPT A. they produce methane from CO2 and H2 B. they live in the intestinal tracts of cows, humans, and termites C. they live in swamps and marshes D. their biogas may contribute to global warming E. they are harmful human pathogens
E
Which of the following is a mismatch? A. thermophiles-live in extremely cold temps B. methanogens-prefer anaerobic environments C. halophiles-live in high salt environments D. thermoacidophiles-live in high temps and acidic environments
A
What is an obligate intercellular parasite?
A parasite that is obligated to live inside a host for survival.
Host Range
Each particular virus can infect cells of only a limited number of host species called the: This specificity is due to "lock and Key" surface proteins. Sometimes limited to certain tissues. They are able to use virally coded RNA polymerases that can use RNA as a template. It uses the host cells and their resources to create new protein capsids.
Eukarya are believed to have diverged from the bacterial line of descent. The Eukarya are, therefore, more closely related to the Bacteria than to the Archaea. True False
False
Eukarya are believed to have diverged from the bacterial line of descent. The Eukarya are, therefore, more closely related to the Bacteria than to the Archaea. True False
False
Plasmids
In addition to is its single chromosome (the nucleoid) a prokarote may also have much smaller rings of independently replicating DNA molecules.
Prions
Infectious proteins that cause many degenerative brain diseases in various animal species. Kuru was discovered in the 1900s in New Guinea in humans. It was a prion spread through cannibalism. They act extremely slowly, (almost ten years before symptoms). Second, they are almost indestructible. Prions transmit by transforming normal proteins into prionic ones.
Phototrophs Chemotrophs Autotrophs Heterotrophs
Organisms that obtain energy from: Light, chemicals, CO2, at least one organic nutrient such as glucose.
Extremophiles
Organisms that survive in extreme conditions
Which type of symbiotic relationship are there no examples of in the domain Archaea?
Parasitism
Heterocysts
Part of a larger filament of cells that utilize photosynthesis, these are highly specialized cells that only carry out nitrogen fixation and intercellular connections help them to transfer fixed nitrogen to other cells.
Temperate Phages
Phages capable of using both modes of replicating within a bacterium are called:
Viral Diseases in Plants
Plant diseases spread by two major routes: Horizontal Transmission- a plant is infected from an external source of the virus (IE a plant is more susceptible if it is damaged from herbivores etc.) Vertical Transmission- A plant inherits a virus from it's parents.
Which of the following is not part of the reproduction cycle of HIV? Biosynthesis of the viral mRNA Reverse transcription of the viral RNA Reverse transcription of the viral DNA Maturation of the viruses
Reverse transcription of the viral DNA
Gram Stain
Scientists can classify many bacterial species into two groups based on cell wall composition. Gram positive: these bacteria have simple walls with a large amount of Peptidoglycan. Gram-Negative: have less Peptidoglycan and are structurally more complex, their membrane contains lipopilysaccharides
Nitrogen fixation
Some cyanobacteria convert atmospheric nitrogen to ammonia. These cells can then incorporate this fixed nitrogen Into amino acids and organic acids.
Parasitism
Some prokaryotes partake in: They eat their host cells contents and tissues. Those that cause disease are known as pathogens.
Fimbriae
Some prokaryotes stick to their substrate or to one another by Hairlike appendages known as:
Which statement is true about prokaryotes? They lack ribosomes. They do not divide by mitosis. They contain a nucleus. They usually lack a cell wall. They contain a long linear strand of DNA as the genetic material.
They do not divide by mitosis.
Genetic diversity in prokaryotes
They reproduce at such a rapid rate, mutations, although not common, come about quick from sheer reproductive capability.
F factor
This consists of about 25 genes, most required for the production of the pili. The ability to form pili and transfer DNA results from this. Cells containing the F plasmid are donors. Homologous regions with the recipients DNA and the F plasmid may result in recombiants.
Bacterial cells pick up free pieces of DNA that were secreted by live bacteria or released from dead bacteria in their environment. This process is called
Transformation
An environmental change, such as exposure to ultraviolet light, may cause a lysogenic bacterium to enter a lytic cycle. True False
True
Prophage
When viral DNA is integrated into bacterial DNA, the viral DNA is known as a: One prophage gene codes for a protein that prevents transcription of most of the other prophage genes. This allows the genes to spread to other cells, until it enters the lytic cycle.
Symbiosis Mutualism Commensalism
Prokaryotes form Close ecological relationships between organisms. Both benefit. One benefits, the other is neutral.
Which of the following is part of a viroid?
RNA
Retroviruses
RNA animal viruses with the most complicated reproductive cycles. They are equipped with reverse transcriptase which transcribes an RNA template into DNA providing a RNA to DNA flow. HIV is a retrovirus
How do bacteria replicate?
Replicate asexually by Binary Fission. Binary Fission: Replicate DNA, one goes to one side of membrane, the other to the other side & they split off into 2 daughter cells.
Halophiles
Require a high salt environment. Have a chloride pump that pumps chloride into the cell. May be chemoheterotrophs or photosynthetic. All of the above choices are correct.
R plasmids
Resistance genes that specifically hinder the effectiveness of certain antibiotics.
What type of virus is in the HIV virus? Why?
Retrovirus (RNA-> cDNA)->Reverse transcription
Which of the following is not part of the reproduction cycle of HIV?
Reverse transcription of the viral DNA
Bacteriophages carry portions of bacterial DNA from one cell to another in a process called
Transduction
A facultative anaerobe is an organism that can metabolize effectively in the presence or absence of oxygen. True False
True
A lichen is a symbiotic relationship between cyanobacteria and fungi. True False
True
A lichen is a symbiotic relationship between cyanobacteria and fungi. True False
True
An environmental change, such as exposure to ultraviolet light, may cause a lysogenic virus to enter a lytic cycle. True False
True
The protective protein coat surrounding the genetic material of a virus:
capsid
A glycocalyx that consists of a well-organized layer of polysaccharide is called a _____, while a loosely organized layer is called a _____.
capsule; slime layer
Which structure of prokaryotic cell prevents the cell from bursting or collapsing due to osmotic pressure changes?
cell wall
Which of these is the best description of a virus?
chemical complexes of RNA or DNA protected by protein shell
An enveloped virus enters a host cell by: injecting its DNA or RNA into the host cell. fusion of its envelope with the host cell's plasma envelope. endocytosis. engulfing the host cell and incorporating its organelles as its own. Both choices B and C are correct choices.
endocytosis.
An internal structure formed by a bacterial cell that functions in dispersal and survival in a harsh environment is called a(n) ______.
endospore
When conditions are unfavorable, some Gram positive bacteria form
endospores
When conditions are unfavorable, some bacteria form
endospores
What is another term for a parasite that causes a disease?
pathogen
Gram positive and Gram negative bacteria stain differently because they have different amounts of _____ in their cell walls.
peptidoglycan
The unique molecule found in bacterial cell walls that is composed of unique combinations of sugars and amino acids:
peptidoglycan
Thermoacidophiles can survive very high temperature due to the unique composition of their:
plasma membrane
Which enzyme enables a retrovirus to convert its' RNA genome into DNA?
reverse transcriptase
Which enzyme enables a retrovirus to convert its' RNA genome into DNA? DNA ligase reverse helicase reverse transcriptase DNA helicase
reverse transcriptase
A bacterium that functions in decomposition by secreting digestive enzymes and absorbing the resulting nutrients into its cell is called a(n) _______.
saprotroph
What is a bacteriophage?
virus that enters a bacterial cell
What is the correct sequence of events in the lytic cycle of a bacteriophage infection? A. Attachment, Viral DNA penetration into host cell, Integration of viral DNA into host cell DNA, Biosythesis, Maturation, Release B. Endocytosis of virion, Uncoating, Maturation, and Release C. Attachment, Fusion of envelope and host cell membrane, Biosynthesis, Maturation, and Release D. Attachment, Viral DNA penetration, Biosynthesis, Maturation and Release
D. Attachment, Viral DNA penetration, Biosynthesis, Maturation and Release
Which of the following characteristics about saprotrophs is NOT true? A. they are viruses that infect plant and fungal cells B. they are bacteria that decompose large organic molecules C. saprotrophs are also called decomposers D. they are ecologically important in recycling matter
A
Which statement is true about prokaryotes? A. They contain a nucleus. B. They lack ribosomes. C. They usually lack a cell wall. D. They do not divide by mitosis. E. They contain a single circular DNA molecule as the genetic material.
D. They do not divide by mitosis.
All of the following are means of genetic recombination in prokaryotes EXCEPT A. conjugation. B. transformation. C. transduction. D. crossing over.
D. crossing over.
Viruses are categorized according to all of the following EXCEPT A. size and shape. B. their type of nucleic acid. C. the presence of absence of an envelope. D. their method of reproduction, whether asexual or sexual.
D. their method of reproduction, whether asexual or sexual.
Influenza strains that sweep around the world often carry names such as Shanghai H1N1 or Mexico City H2N2. The viruses vary in H and N surface proteins because A. the viruses reproduce and attack people in cities more often. B. these viruses emerged as stray DNA from the genomes of people in these cities. C. this is where the antibodies of immune people began to break down and the old virus was again virulent. D. when infected people develop immunity to the present virus, strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas.
D. when infected people develop immunity to the present virus, strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas.
Which of these is the best description of a virus? A. a noncellular living organism B. on of the smallest bacteria known C. a member of the kingdom Virusae D. a cell at the boundary between living and nonliving things E. chemical complexes of RNA or DNA protected by protein shell
E
Which statement is true about prokaryotes? A. they contain a nucelus B. they lack ribosomes C. they usually lack a cell wall D. they do not divide by mitosis E. they contain a long linear strand of DNA as the genetic material
E
An enveloped virus enters a host cell by A. injecting its DNA or RNA into the host cell. B. fusion of its envelope with the host cell's plasma envelope. C. endocytosis. D. Any of the above choices are correct. E. B and C only are correct.
E. B and C only are correct.
Taxis
A directed movement toward or away from a stimuli.
Epidemic
A general outbreak. A global epidemic is a pandemic.
Vaccine
A harmless variant or derivative of a pathogen that stimulates the immune system to mount defenses against the harmful pathogen.
Explain how a bird flu virus can infect a human.
A mutation of the bird flu virus may occur either in the original host or new host. the cell mutates to contain both the bird & human spikes.
Lytic Cycle
A phage (bacteriophage) replicative cycle that culminates in death of the host cell is known as a:
Virulent Phage
A phage that only replicates using a lytic cycle is a virulent phage.
Which of the following characteristics about saprotrophs is NOT true? A. They are viruses that infect plant and fungal cells. B. They are bacteria that decompose large organic molecules. C. Saprotrophs are also called decomposers. D. They are ecologically important in recycling matter.
A. They are viruses that infect plant and fungal cells.
Some, but not all, virus capsids are surrounded by ________. A. a membranous envelope B. both DNA and RNA C. either DNA or RNA D. a protein capsid E. a protein spore coat
A. a membranous envelope
Study the life cycle diagram. Label B is the ________ life cycle. A. lysogenic B. sexual C. lytic D. alternation of generations
A. lysogenic
The cycle of viral infection in which the viral DNA is integrated into the bacterial DNA is called the _______ cycle. A. lysogenic B. lysozyme C. lytic D. lysol E. lysosome
A. lysogenic
Which of the following is a mismatch? A. thermophiles - live in extremely cold temperatures. B. methanogens - prefer anaerobic environments C. halophiles - live in high salt environments D. thermoacidophiles - live in high temperatures and acidic environments
A. thermophiles - live in extremely cold temperatures.
Bacterial cells pick up free pieces of DNA that were secreted by live bacteria or released from dead bacteria in their environment. This process is called A. transformation. B. transduction. C. conjugation. D. infection. E. replication.
A. transformation.
A circular piece of RNA that interrupts the normal regulatory systems in plants, thereby causing disease is a A. viroid. B. prion. C. plant virus. D. bacterium.
A. viroid.
What is a plasmid?
Accessory rings of DNA
Halophiles Require a high salt environment. Have a chloride pump that pumps chloride into the cell. May be chemoheterotrophs or photosynthetic. All of the above choices are correct. Require a high temperature in order to survive
All of the above choices are correct.
Similarities between the archaea and eukarya include same ribosomal proteins. similar tRNA. similar initiation of transcription. All of the choices are correct similarities. same ribosomal proteins and different initiation of transcription.
All of the choices are correct similarities.
Lysogenic Cycle
Allows replication of the phage genome without destroying the host.
Treatments once you are infected
Antibiotics inhibit key bacterial antibiotics, not viral or eukaryotic enzymes. Some treatments inhibit enzymes that play a role in viral enzyme construction.
Pili
Appendages that pull two cells prior to DNA transfer from one cell to the other.
What are the two Domains that the prokaryotes are classified under?
Archaea & Bacteria
What are the two Domains that the prokaryotes are classified under? Archaea & Eukarya Protista & Archaea Eukarya & Bacteria Archaea & Bacteria
Archaea & Bacteria
Methanogens
Archaea that release methane as a by-product of their unique ways of obtaining energy.
What is the correct sequence of events in the lytic cycle of a bacteriophage infection?
Attachment, Viral DNA penetration, Biosynthesis, Maturation and Release
What is the correct sequence of events in the lytic cycle of a bacteriophage infection? Attachment, Fusion of envelope and host cell membrane, Biosynthesis, Maturation, and Release Attachment, Viral DNA penetration into host cell, Integration of viral DNA into host cell DNA, Biosythesis, Maturation, Release Endocytosis of virion, Uncoating, Maturation, and Release Attachment, Viral DNA penetration, Biosynthesis, Maturation and Release
Attachment, Viral DNA penetration, Biosynthesis, Maturation and Release
An enveloped virus enters a host cell by A. injecting its DNA or RNA into the host cell B. fusion of its envelope with the host cell's plasma envelope C. endocytosis D. any of the choices are correct E. attaching to the host cell's membrane and then injecting its DNA or RNA into the host cell
B
Identify the correct sequence of events that occur during the reproduction of HIV A. virus attaches to a host cell-the virus enters the cell-viral DNA is incorporated into the host DNA-reverse transcriptase occurs-viral/host DNA is turned into a viral mRNA code-the viral RNA forms into a mature virus-mature viruses leave the host cell B. virus attaches to a host cell-the virus enters the cell- reverse transcriptase occurs-viral DNA is incorporated into the host DNA-viral/host DNA is turned into a viral mRNA code-the viral RNA forms into a mature virus-mature viruses leave the host cell C. Virus attaches to a host cell-the virus enters the cell-viral DNA is incorporated into the host DNA-reverse transcriptase occurs-the viral RNA forms into a mature virus-viral/host DNA is turned into a viral mRNA code-mature viruses leave the host cell D. viruse attaches to a host cell-the virus enters the cell-viral/host DNA is turned into a viral mRNA code-viral DNA is incorporated into the host DNA-reverse transcriptase occurs-the viral RNA forms into a mature virus-mature viruses leave the host cell
B
If a virus is latent, it A. cannot be a retrovirus B. is not actively replicating C. has not entered a lysogenic cycle D. is gaining a new envelope via "budding" E. is easy to develop immunity against it
B
In order to infect a cell, a virus must A. inject its protein into the cell while the nucleic acid remains attached to the host cell surface B. have a special protein on its surface that can interact with a protein on the surface of the host cell C. actively burrow through the cell wall membrane of the host cell to reach the cell's nucleus D. produce a special extension of its cytoplasm when it comes into contact with the appropriate host cell
B
Which of the following is not part of the reproduction cycle of HIV? A. reverse transcription of the viral RNA B. reverse transcription of the viral DNA C. maturation of the viruses D. Biosynthesis of the viral mRNA
B
This bioterrorist agent was sent through the mail and inhaled to produce illness and death in five people. It produces endospores and is called A. Clostridium tetani. B. Bacillus anthracis. C. Vibrio cholera. D. Staphylococcus aureus.
B. Bacillus anthracis.
The innermost portion of a virus' structure is made up of A. a membranous envelope. B. either DNA or RNA. C. both DNA and RNA. D. a protein capsid. E. spikes.
B. either DNA or RNA.
When conditions are unfavorable, some Gram positive bacteria form A. pili. B. endospores. C. galls D. capsules. E. thylakoids.
B. endospores.
If a virus is latent, it A. cannot be a retrovirus. B. has not entered a lytic cycle. C. has not entered a lysogenic cycle. D. is gaining a new envelope via "budding." E. is easy to develop immunity against it.
B. has not entered a lytic cycle.
In order to infect a cell, a virus must A. inject its protein into the cell while the nucleic acid remains attached to the host cell surface. B. have a special protein on its surface that can interact with a protein on the surface of the host cell. C. actively burrow through the cell wall or cell membrane of the host cell to reach the cell's nucleus. D. produce a special extension of its cytoplasm when it comes into contact with the appropriate host cell.
B. have a special protein on its surface that can interact with a protein on the surface of the host cell.
Which of the following is not a viral disease? A. AIDS B. tetanus C. Ebola Hemorrhagic fever D. West Nile Encephalitis
B. tetanus
Bacteriophages carry portions of bacterial DNA from one cell to another in a process called A. transformation. B. transduction. C. conjugation. D. infection. E. replication.
B. transduction.
Endospores
Bacteria develop resistant cells when they lack an essential nutrient. A cell lyses releasing the endospore after dehydrating the endospore and halting its metabolism.
Which of the following does not match a type of virus to its specific type of host cell?
Bacteriophage-lung cells
Which group of Archaea are chemoautotrophic anaerobes that will use hydrogen as an electron donor? A. halophiles B. methanogens C. thermoacidophiles D. cyanobacteria
C
Which statement is NOT true about a retrovirus? A. it may cause cancer or AIDS B. it contains reverse transcriptase C. It remains in the host cell genome, but is not replicated when host DNA is replicated D. It has the capacity to integrate cDNA into the host DNA of the cell it infects
C
Which statement is NOT true about a retrovirus? A. It may cause cancer or AIDS. B. It contains reverse transcriptase. C. It remains in the host cell genome, but is not replicated when host DNA is replicated. D. It has the capacity to integrate cDNA into the host DNA of the cell it infects.
C. It remains in the host cell genome, but is not replicated when host DNA is replicated.
Which of these diseases could NOT be treated with antibiotics? A. chlamydia B. plague C. influenza D. scarlet fever
C. influenza
Study the life cycle diagram. Label A is the ________ life cycle. A. lysogenic B. sexual C. lytic D. alternation of generations
C. lytic
The cycle of viral infection of a bacterial cell that will cause its death most rapidly is called the _______ cycle. A. lysogenic B. lysozyme C. lytic D. lysol E. lysosome
C. lytic
Pasteur chose the Latin root word for "virus" meaning A. extremely small. B. non-living. C. poison. D. contagious. E. particle.
C. poison.
Capsule
Cell wall in prokaryotes surrounded by a sticky layer called a: Composed of polysaccharides or protein.
Viroids
Circular RNA molecules , only a few hundred nucleotides long, that infect plants. They do not encode proteins, but rather, replicate in host plant cells and cause errors in regulatory systems that control growth.
All of the following are menas of genetic recombinations in prokaryotes EXCEPT A. conjugation B. transformation C. transduction D. crossing over
D
Chemoautotrophs oxidize which of the following to obtain the energy necessary to reduce carbon dioxide to an organic compound? A. hydrogen gas B. hydrogen sulfide C. ammonia D. all of the choices are correct E. nitrites
D
Halophiles A. require a high salt environment B. increase the chloride level within their cells C. may be chemoheterotrophs or photosynthetic D. all of the choices are correct E. use bacteriorhodospin to capture solar energy
D
Influenza strains that sweep around the world often carry names such as Shanghai H1N1 or Mexico City H2N2.The viruses vary in H and N surface proteins because A. the viruses reproduce and attack people in cities more often B. these viruses emerged as stray DNA from the genomes of people in these cities C. this is where the antibodies of immune people began to break down and the old virus was again virulent D. when infected people develop immunity to the present virus, strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas
D
Prokaryotes generally range in size from A. 10-400 nm B. 20-300 mn C. 10-100 um D. 1-10 um E. 50-100 nm
D
Similarities between the archaea and eukarya include A. same ribosomal proteins B. similar tRNA C. similar initiation of transcription D. all of the choices are correct similarities E. are closer related to each other than to the bacteria
D
What is the correct sequence of events in the lytic cycle of a bacteriophage infection? A. Attachement, Viral DNA penetration into host cell, Integration of viral DNA into host cell DNA, Biosynthesis, Maturation, Release B. Endocytosis of virion, Uncoating, Maturation, and Release C. Attachment, Fusion of envelope and host cell membrane, Biosynthesis, Maturation, and Release D. Attachement, Viral DNA penetration, Biosynthesis, Maturation and Release
D
Which of the following could be used to grow lysogenic viruses in the laboratory? A. chicken eggs B. cell culture C. bacteria D. all of the choices could be used
D
Prokaryotes generally range in size from A. 10-400 nm. B. 20-300 mm. C. 10-100 µm. D. 1-10 µm. E. 50-100nm
D. 1-10 µm.
Chemoautotrophs oxidize which of the following to obtain the energy necessary to reduce carbon dioxide to an organic compound? A. hydrogen gas B. hydrogen sulfide C. ammonia D. All of the above choices are correct. E. A and C only.
D. All of the above choices are correct.
Halophiles A. require a high salt environment. B. have a chloride pump that pumps chloride into the cell. C. may be chemoheterotrophs or photosynthetic. D. All of the above choices are correct. E. A and C only are correct.
D. All of the above choices are correct.
Similarities between the archaea and eukarya include A. same ribosomal proteins. B. similar tRNA. C. similar initiation of transcription. D. All of the choices are correct similarities. E. A and B only.
D. All of the choices are correct similarities.
Which of the following characterize prions? A. Prions are proteinaceous infectious particles. B. Prions cause TSEs, transmissible spongiform encephalopathies. C. Prions are misshapen proteins that may interact with a normal prion protein to change its shape. D. All of the choices are correct. E. A and B only.
D. All of the choices are correct.
Which of the following could be used to grow viruses in the laboratory? A. chicken eggs B. cell culture C. bacteria D. All of the choices could be used.
D. All of the choices could be used.
Which of these is the best description of a virus? A. a noncellular living organism B. one of the smallest bacteria known C. a member of the kingdom Virusae D. a cell at the boundary between living and nonliving things E. chemical complexes of RNA or DNA protected by protein shell
E. chemical complexes of RNA or DNA protected by protein shell
All of the following are true of methanogens EXCEPT A. they produce methane from CO2 and H2. B. they live in the intestinal tracts of cows, humans, and termites. C. they live in swamps and marshes. D. their biogas may contribute to global warming. E. they are harmful human pathogens.
E. they are harmful human pathogens.
The thermoacidophiles living in hot springs would be classified as:
archaeans
A virus that infects only bacterial cells is called a(n)
bacteriophage
Most prokaryotes reproduce via:
binary fission
A dramatic increase in cyano bacterial numbers in a lake as a result of human pollution is called a cyanobacterial _____
bloom
Which of these is the best description of a virus? a cell at the boundary between living and nonliving things a member of the kingdom Virusae a noncellular living organism one of the smallest bacteria known chemical complexes of RNA or DNA protected by protein shell
chemical complexes of RNA or DNA protected by protein shell
A bacterium that needs to take in organic nutrients to survive is called a ______
chemoautotroph.
Which of the following could be used to grow lysogenic viruses in the laboratory?
chicken eggs cell culture bacteria All of the choices could be used.
The innermost portion of a virus' structure is made up of
either DNA or RNA.
The innermost portion of a virus' structure is made up of a membranous envelope. a protein capsid. both DNA and RNA. either DNA or RNA. spikes. References Multiple Choice
either DNA or RNA.
A newly identified virus that becomes more prominent because of its ability to cause serious disease is a (n) _____ virus.
emerging
When conditions are unfavorable, some Gram positive bacteria form capsules. thylakoids. endospores. galls. pili.
endospores.
The short bristle-like fibers that may allow a prokaryote to attach to the surface of a host cell are called:
fimbriae
The structure that rotates 360 degrees to allow for cellular movement is called a
flagellum
What is a prokaryote?
fully functioning cells (includes bacteria & archaea) that lack a membrane bound nucleus.
An enveloped virus enters a host cell by
fusion of its envelope with the host cell's plasma envelope.
If a virus is latent, it
has not entered a lytic cycle.
If a virus is latent, it has not entered a lytic cycle. has not entered a lysogenic cycle. cannot be a retrovirus. is easy to develop immunity against it. is gaining a new envelope via "budding." References Multiple Choi
has not entered a lytic cycle.
The cycle of viral infection of a bacterial cell that will cause its death most rapidly is called the _______ cycle. lysogenic lysol lytic lysozyme lysosome
lytic
Biogas, produced by _____ contributes to 65% of the methane gas in our atmosphere which is contributing to the greenhouse effect an global warming
methanogens
A cytoplasmic region of prokaryotic cells where chromosomal DNA is located:
nucleoid
An organism that cannot grow in the presence of oxygen gas is a(n):
obligate anaerobe
What is a saprotroph?
organism that feeds on deceased organisms- Aka: decomposers
A _____ is any organism that causes disease, including parasitic bacteria.
pathogen
Pasteur chose the Latin root word for "virus" meaning
poison
Pasteur chose the Latin root word for "virus" meaning non-living. poison. particle. extremely small. contagious.
poison.
Infectious particle consisting of protein only and no nucleic acid (usually associated with mad cow disease):
prion
The term ____ refers to any organism that has neither a nucleus nor cytoplasmic organelles beyond ribosomes.
prokaryote
Bacteria are classified as _____ cells
prokaryotic
A virus with a RNA genome that utilizes reverse transcriptase is a:
retrovirus
The viral enzyme found in retroviruses that is capable of converting their RNA genome into a DNA copy is called ______ ______.
reverse transcriptase
The disease that results from bacterial infection that involved sustained muscle contraction without relaxation is called _____.
tetanus
Which bacteriophage life cycle can result in the formation of a prophage, latent viral DNA that is replicated along with the host DNA?
the lysogenic cycle
Viruses are categorized according to all of the following EXCEPT
their method of reproduction, whether asexual or sexual.
Viruses are categorized according to all of the following EXCEPT their type of nucleic acid. size and shape. the presence of absence of an envelope. their method of reproduction, whether asexual or sexual.
their method of reproduction, whether asexual or sexual.
The type of Archaea that lives in hot , acidic, aquatic habitats, such as hot springs or near hydrothermal vents is called a ___.
thermoacidophile
Which of the following is a mismatch?
thermophiles - live in extremely cold temperatures
Which of the following is a mismatch? methanogens - prefer anaerobic environments halophiles - live in high salt environments thermophiles - live in extremely cold temperatures thermoacidophiles - live in high temperatures and acidic environments
thermophiles - live in extremely cold temperatures
All of the following are true of methanogens EXCEPT
they are harmful human pathogens.
All of the following are true of methanogens EXCEPT they live in swamps and marshes. their biogas may contribute to global warming. they are harmful human pathogens. they live in the intestinal tracts of cows, humans, and termites. they produce methane from CO2 and H2.
they are harmful human pathogens.
A poisonous substance produced by living cells or organisms that is capable of causing disease on contact with or absorption by body tissue is a(n):
toxin
Bacteriophages carry portions of bacterial DNA from one cell to another in a process called
transduction
Bacteriophages carry portions of bacterial DNA from one cell to another in a process called conjugation. replication. transduction. infection. transformation.
transduction
Bacterial cells pick up free pieces of DNA that were secreted by live bacteria or released form dead bacteria in their environment. This process is called
transformation
_____ occurs when a cell takes on extracellular pieces of DNA.
transformation
Bacterial cells pick up free pieces of DNA that were secreted by live bacteria or released from dead bacteria in their environment. This process is called transduction. conjugation. infection. transformation. replication.
transformation.
A facultative anaerobe is an organism that can metabolize effectively in the presence or absence of oxygen. True False
true
A non cellular parasitic agent consisting of an outer proteinaceous capsid and an inner core of nucleic acid.
virus
AIDS, polio, rabies and the common cold are all examples of infectious diseases which are caused by:
viruses
What are the three shapes of bacteria?
1.) Cocci (round) 2.) Bacilli (rod) 3.) Spirilli (spiral)
Describe the three methods of genetic transformation.
1.) Conjugation: Conjugation plus forms b/t 2 cells & DNA is transferred. 2.) Transformation: Bacterium picks up pieces of DNA from other prokaryotes. 3.) Transduction: Bacteriophages serves as vectors that carry portions of bacterial DNA from cell to cell.
Name three common viruses that infect humans.
1.) Flu 2.) Small pox 3.) Common cold
What three traits are used to categorize viruses? Describe them.
1.) Obligate- viruses are obligated to attach to a host in order to survive/ live 2.) Intracellular- live inside the host cell 3.) Parasite-is a parasite to the host
List three diseases that are associated with bacteria.
1.) Salmonella 2.) E. colli 3.) Tethis
On average, the size of virus is about ______
10-400 nm
Ivanowsky first recognized that something smaller than a bacterium, called a filterable virus, was able to cause disease in the year
1892
Ivanowsky first recognized that something smaller than a bacterium, called a filterable virus, was able to cause disease in the year 1965. 2001. 1650. 1892. 1700.
1892
Emergence of Viruses
3 Ways a virus can appear suddenly: 1. Mutation of existing viruses (RNA viruses have an unusually high mutation rate because they have no proofreading) 2. Viruses are sometimes extant, but isolated in a small population. 3. Spread of extant viruses from animals.
Some, but not all, virus capsids are surrounded by ______
a membranous envelope
Some, but not all, virus capsids are surrounded by _________.
a membranous envelope
Some, but not all, virus capsids are surrounded by _________. a protein capsid both DNA and RNA a membranous envelope a protein spore coat either DNA or RNA
a membranous envelope
Prokaryotes are now divided into the
archaea and bacteria
______ result from a symbiotic relationship between certain fungi and algae, in which the fungi possible provide inorganic food or water and the algae provide organic food from photosynthesis.
lichens
A host that carries a prophage is called a ____ cell.
lysogenic
Study the life cycle diagram. Label B is the _____ life cycle.
lysogenic
Study the life cycle diagram. Label B is the ________ life cycle.
lysogenic
Study the life cycle diagram. Label B is the ________ life cycle. lytic alternation of generations sexual lysogenic
lysogenic
The cycle of viral infection in which the viral DNA is integrated into the host's DNA is called the _____ cycle.
lysogenic
The cycle of viral infection in which the viral DNA is integrated into the host's DNA is called the _______ cycle. lysogenic lysosome lysozyme lysol lytic
lysogenic
Study the life cycle diagram. Label A is the _____ life cycle.
lytic
Study the life cycle diagram. Label A is the ________ life cycle.
lytic
Study the life cycle diagram. Label A is the ________ life cycle. lysogenic alternation of generations lytic sexual
lytic
The cycle of viral infection of a bacterial cell that will cause its death most rapidly is called the ______ cycle
lytic
H1N1
Hemagglutinin and Neuraminidase. 16 and 9 types of proteins respectively.
Which type of bacteria is photoautotrophic?
cyanobacteria
Influenza strains that sweep around the world often carry names such as Shanghai H1N1 or Mexico City H2N2. The viruses vary in H and N surface proteins because when infected people develop immunity to the present virus, strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas. these viruses emerged as stray DNA from the genomes of people in these cities. the viruses reproduce and attack people in cities more often. this is where the antibodies of immune people began to break down and the old virus was again virulent.
when infected people develop immunity to the present virus, strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas.
Identify the labeled features of the typical prokarytoic cell: A B C D E
-Fimbriae -Nucleoid -Conjugation Pilus -Flagellum -Cytoplasm
Spiral-shaped bacteria Rod-shaped bacteria forming a chain round bacteria forming a cluster
-Spirillum -Streptobacilli -Staphylococci
Commensalism Parasitism Mutualism
-Symbiotic relationship in which one species is benefited, and the other is neither harmed nor benefited. -Symbiotic relationship in which one species benefits while harming the other. -Symbiotic relationship in both species benefit from the association.
Which of the following are found in all viruses?
-capsid -nucleic acid core -proteins
In the laboratory, viruses are often maintained using:
-chicken embryos -tissue culture
Which are the common methods by which a virus can rapidly " emerge" and cause human illness?
-extension of the viral range -viral mutataion
Archaeans differ from bacteria in that their cell membranes have unusual ____, and their cell walls do not contain ____.
-lipids -peptidoglycan
The main classes of antibiotics function to inhibit the photosynthesis of which of the following?
-protein -cell wall
Which of the following are similarities between domains Archaea and Eukarya?
-ribosomal proteins -types of tRNA -initiation of transcription
Which of the following are criteria for categorizing viruses?
-type of nucleic acid -presense of envelope -size and shape
Why are viruses considered non-living?
-viruses do not respond to stimuli -viruses require a host cell to replicate -viruses cannot carry out their own metabolic functions.
Place the following substance in the correct order as they are transformed by nitrifying bacteria:
1 Ammonia (NH3) 2 Nitrites (NO2) 3 Nitrates (NO3)
List the steps of viral lytic cycle in the correct sequence:
1 Attachment 2 Penetration 3 Biosynthesis 4 Maturation 5 Release
List the following from smallest to largest:
1 viroid 2 virus 3 prokaryote 4 eukaryote
Prokaryotes generally range in size from 10-400 nm. 50-100nm. 10-100 µm. 20-300 mm. 1-10 µm.
1-10 µm.
Describe the five stages of the lytic cycle.
1.) Attachment 2.) Penetration 3.) Biosynthesis 4.) Maturation 5.) lysis
What is a plasmid?
Extrachromosomal loops of DNA that usually carry accessory genes.
What is another name for archaea? List the three types and the conditions they require
Extremophiles 3 types of conditions they live in: 1.) Anaerobic Marshes: produce methane from hydrogen & c02. 2.) Salty lakes- high salt concentration for growth. 3.) Hot sulfur springs- Thermoacidophiles: reduce sulfides & survive best in very high temps. Plasma membranes: contain unusual lipids to aid survival.
A Gram-negative bacteria will have a peptidoglycan layer that is sandwiched between two plasma membranes and will stain purple. True False
False
A prophage is a form of virus that attacks only plants cells. True False
False
Which description best describes the cell wall of a Gram-positive bacteria?
It is composed of a single plasma membrane and a thick outer layer of peptidoglycan.
Which description best describes the cell wall of a Gram-positive bacteria? It is composed of a single plasma membrane and a thin outer layer of peptidoglycan. It is composed of a double layer in the plasma membrane and a thin outer layer of peptidoglycan. It is composed of a double layer in the plasma membrane and a thick outer layer of peptidoglycan. It is composed of a single plasma membrane and a thick outer layer of peptidoglycan. It is composed of a single plasma membrane and a thin outer layer of cellulose.
It is composed of a single plasma membrane and a thick outer layer of peptidoglycan.
Which statement is NOT true about a retrovirus? It remains in the host cell genome, but is not replicated when host DNA is replicated. It contains reverse transcriptase. It has the capacity to integrate cDNA into the host DNA of the cell it infects. It may cause cancer or AIDS.
It remains in the host cell genome, but is not replicated when host DNA is replicated.
Who was the first person to suggest the existence of a virus, suspecting that it was the cause of rabies?
Louis Pasteur
Which of these best describe a photoautotroph?
Organisms able to synthesize organic molecules by using carbon dioxide as the carbon source and sunlight as the energy source.
Viral Envelopes
Membranous envelopes that surrounds the capsids of influenza viruses and many other viruses.
Biofilms
Metabolic cooperation between different prokaryotic species often occurs In surface-coating colonies known as:
Peptidoglycan
Most bacterial cell walls contain modified sugars cross-linked by peptides known as: In contrast to the chitin or cellulose of most plants or fungi.
Bacteriophages
Most complex capsids are found on these. The bacteriophages are named T-#
Bacterial Flagellum
Most likely an analogous structure. Composed of a Motor, Hook, and filament. Only roughly 21 of 42 proteins are required, and 19 of those are used elsewhere in the cell. It most likely evolved from an ancient Secretory system. (Exapation: something evolves from previous structure)
Restriction Enzymes
Natural selection favors bacterial mutants with incompatible receptors for viruses. And when phage DNA enters a bacterium, The DNA is often identified as foreign and is cut up by enzymes.
Which of these best describe a chemoautotroph?
Organism able to synthesize organic molecules by using carbon dioxide as the carbon source and the oxidation of an inorganic substance (such as hydrogen sulfide) as the energy source.
The cycle of viral infection of a bacterial cell that will cause its death most rapidly is called the _______ cycle.
lytic
Provirus
The Integrated DNA (from a retrovirus) is known as a: and never leaves the host's cell. In contrast, a prophage leaves the host cell at the start of the lytic cycle). The host's RNA polymerase transcribes the proviral DNA into RNA which can synthesize new viral proteins or act as genomes for new viruses.
Viral Genome
The Viral genome can be composed of RNA or DNA and whether or not it is double or single stranded. This helps classify viruses.
Genetic recombination in Prokaryotes
The combining of DNA from two different sources. Transformation: the genotype and phenotype of a cell are altered by the uptake of foreign DNA from its surroundings. (homologous DNA exchange) Transduction: phages carry prokaryotic genes from one host cell to another. Conjugation:DNA is transferred between two prokaryotic cells that are temporarily joined.
Explain the difference between the lytic and lysogenic cycles.
The lytic cycle has immediate viral reproduction, whereas in the lysogenic cycle, the virus lays dormant.
Prokaryotes are now divided into the bacteria and cyanobacteria. archaea and cyanobacteria. photosynthetic bacteria and chemosynthetic bacteria. autotrophs and heterotrophs. archaea and bacteria.
archaea and bacteria
Capsid
The protein shell enclosing the viral genome is called a: Built from protein subunits called capsomeres. Viruses have distinct shapes, Helical (rod), Icosahedral (Circle-ish with spikes on each vertex), Membranous glycoprotein studded, and Icosahedral head with a tail.
Bioremediation
The use of organisms to remove pollutants from soil, air, or water.
What are the two domains that the prokaryotes are classified under?
archaea and bacteria
Which group of Archaea are chemoautotrophic anaerobes that will use hydrogen as an electron donor? Methanogens Thermoacidophiles Cyanobacteria Halophiles
Thermoacidophiles
Pathogenic prokaryotes
These cause illness usually through exotoxins (proteins secreted by Bacteria and other Organisms) or endotoxins (lipopolysaccharide components of The outermembrane of gram-negative bacteria).
Extreme halophiles
These live in highly saline environments.
Extreme thermophiles
These thrive in very hot environments.
Which of the following characteristics about saprotrophs is NOT true?
They are viruses that infect plant and fungal cells.
Which of the following characteristics about saprotrophs is NOT true? They are ecologically important in recycling matter. They are bacteria that decompose large organic molecules. They are viruses that infect plant and fungal cells. Saprotrophs are also called decomposers.
They are viruses that infect plant and fungal cells.
Identify the correct sequence of events that occur during the reproduction of HIV. Virus attaches to a host cell - the virus enters the cell - reverse transcriptase occurs - viral DNA is incorporated into the host DNA - viral / host DNA is turned into a viral mRNA code - the viral RNA forms into a mature virus - mature viruses leave the host cell Virus attaches to a host cell - the virus enters the cell - viral DNA is incorporated into the host DNA - reverse transcriptase occurs - the viral RNA forms into a mature virus - viral / host DNA is turned into a viral mRNA code - mature viruses leave the host cell Virus attaches to a host cell - the virus enters the cell - viral DNA is incorporated into the host DNA - reverse transcriptase occurs - viral / host DNA is turned into a viral mRNA code - the viral RNA forms into a mature virus - mature viruses leave the host cell Virus attaches to a host cell - the virus enters the cell - viral / host DNA is turned into a viral mRNA code - viral DNA is incorporated into the host DNA - reverse transcriptase occurs - the viral RNA forms into a mature virus - mature viruses leave the host cell
Virus attaches to a host cell - the virus enters the cell - reverse transcriptase occurs - viral DNA is incorporated into the host DNA - viral / host DNA is turned into a viral mRNA code - the viral RNA forms into a mature virus - mature viruses leave the host cell
Evolution of Viruses
Viruses infect every form of life: no exceptions. It is possible they evolved from mobile genetic elements, Transposons or plasmids. Scientists believe they originate from naked bits of cellular nucleic acid that move from one cell to another. Capsids evolved to help infect other cells.
Viral Diseases in Animals
Viruses produce symptoms in some ways: Killing lysosomes releasing hydrolytic enzymes. Some cause cells to produce toxins, some are simply composed of molecular components that are toxic. Some symptoms are bodily responses. People can usually heal because of cell division renewing cells, unless it attacks undividing cells.
Viral Envelope
Viruses use their outer membranes (envelopes) to enter a host cell. They generally have viral glycoproteins. The viral envelopes being created within the host are made form the host's plasma membrane. This replicative cycle does not necessarily kill the host cell. Herpes viruses actually get theirs from the golgi.
All of the following are means of genetic recombination in prokaryotes EXCEPT
crossing over.
All of the following are means of genetic recombination in prokaryotes EXCEPT conjugation. crossing over. transduction. transformation.
crossing over.
The innermost portion of a virus' structure is made up of
either DNA or RNA
In order to infect a cell, a virus must
have a special protein on its surface that can interact with a protein on the surface of the host cell.
In order to infect a cell, a virus must have a special protein on its surface that can interact with a protein on the surface of the host cell. inject its protein into the cell while the nucleic acid remains attached to the host cell surface. produce a special extension of its cytoplasm when it comes into contact with the appropriate host cell. actively burrow through the cell wall or cell membrane of the host cell to reach the cell's nucleus.
have a special protein on its surface that can interact with a protein on the surface of the host cell.
The specialized cells found in some colonial cyanobacteria where nitrogen fixation occurs are called what?
heterocysts
Chemoautotrophs oxidize which of the following to obtain the energy necessary to reduce carbon dioxide to an organic compound?
hydrogen gas hydrogen sulfide ammonia All of the above choices are correct.