Bio 2 Chapter 25, 26, 27, and 28

If the half-life of carbon-14 is about 5,730 years, then a fossil that has 1/16 of the normal proportion of carbon-14 to carbon-12 should be about how many years old? - 22,900 - 16,800 - 2,800 - 11,200

*22,900

Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia and Antarctica. The animal apparently lived in arid regions and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous period. Some dicynodonts had two large tusks, extending down from their upper jaws. The tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record in sedimentary rocks, these pig-sized organisms were the most common mammal-like reptiles of the Permian. What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth? 1. origin of mitochondria 2. origin of multicellular eukaryotes 3. origin of chloroplasts 4. origin of cyanobacteria 5. origin of fungal-plant symbioses - 4, 1, 2, 3, 5 - 4, 3, 1, 5, 2 - 4, 3, 2, 1, 5 - 4, 1, 3, 2, 5

*4, 1, 3, 2, 5

The age of the Earth according to modern estimations is about - 1.5 billion years - 3.5 billion years - 8 billion years - 4.6 billion years

*4.6 billion years

A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of farther back helped make possible the evolution of the tetrapod limb . This type of change is illustrative of ______________ - Heterochrony - A change in a developmental gene or its regulation that altered the spatial organization of body parts - The influence of environment on development - Paedomorphosis

*A change in a developmental gene or its regulation that altered the spatial organization of body parts

Which of the following organisms would be most likely to form a fossil? - A rare squirrel - A common worm - A common squirrel - A rare worm

*A common squirrel

The common characteristic of Alveolata is - A layer of flattened vesicles beneath the plasma membrane - Silica covering - Funnel-shaped, contractile collar - A single, unique mitochondria

*A layer of flattened vesicles beneath the plasma membrane

Prokaryotes differ in several ways from eukaryotes; one of the most distinctive is - The ability to reproduce - A nucleus that encloses the cell's DNA - The absence of a plasma membrane - Having hereditary material composed of DNA

*A nucleus that encloses the cell's DNA

Which of the following is a defining characteristic that all protocells had in common? - The ability to replicate RNA - The ability to synthesize enzymes - A surrounding membrane or membrane-like structure - RNA genes

*A surrounding membrane or membrane-like structure

What best describes whether a virus is likely to infect a particular cell? - If a host cell is weakened, viruses are likely to infect it - Viruses only attack epithelial cells, such as the cells lining the lungs - A virus will only infect host cells with the correct surface receptors - Viruses infect the first cells they encounter

*A virus will only infect host cells with the correct surface receptors

Which statement about bacteria is incorrect? - Bacteria are prokaryotes - A bacterial cell has one chromosome - Bacterial cells reproduce by binary fission - All bacteria are pathogenic to humans

*All bacteria are pathogenic to humans

A female fly, full of fertilized eggs, is swept by high winds to an island far out to sea. She is the first fly to arrive on this island and the only fly to arrive in this way. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species, each of which eats only a certain type of food. None of the species can fly, and their balancing organs ( halteres ) are now used in courtship to displays . The male members of each species bear modified halteres that are unique in appearance to their species . Females bear vestigial halteres . The ranges of all of the daughter species overlap In each fly species, the entire body segment that gave rise to the original flight wings is missing. The mutation(s) that led to the flightless condition could have __________ - Duplicated all of the Hox genes in these flies' genomes - Altered the expression of a Hox gene - Originated in another species - Resulted in paedomorphosis

*Altered the expression of a Hox gene

The members of _____________ include dinoflagellates, apicomplexans, and ciliates

*Alveolata

Which of the following was produced in experiments on primitive Earth conditions conducted by Miller-Urey and others? - Amino acids - Ammonia and hydrogen sulfide - Ammonia and water - Methane and oxygen

*Amino acids

Which of the following statements best reflects what we know about how the flu virus moves between species? - An animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates, the virus is passed to a new species such as a bird, and the virus mutates again and can now be transmitted to humans - An influenza virus gains new sequences of DNA from another virus, such as a herpesvirus; this enables it to be transmitted to a human host - A flu virus from a human epidemic or pandemic infects birds; the birds replicate the virus differently and then pass it back to humans - The flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected

*An animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates, the virus is passed to a new species such as a bird, and the virus mutates again and can now be transmitted to humans

The domain most similar to Eukarya is______________

*Archaea

Viral classification and biology has been challenging; presently, most biologists agree that viruses - Should be classified as members of the kingdom Protista - Should be classified as autochemotrophic - Use a photosynthetic process more similar to bacteria than plants - Are constructed from a protein wrapped around DNA or RNA

*Are constructed from a protein wrapped around DNA or RNA

Unlike bacteria, archaea - Are thought to be closely related to eukaryotes - Are prokaryotes - Have cell walls - Have two plasma membranes

*Are thought to be closely related to eukaryotes

Which is the correct order of events in the lytic cycle of a bacteriophage - Integration-penetration-biosynthesis maturation-release - Attachment-integration-biosynthesis-maturation-release - Penetration-attachment-biosynthesis-release-maturation - Attachment-penetration-biosynthesis-maturation-release

*Attachment-penetration-biosynthesis-maturation-release

Which of the three domains contain(s) prokaryotic organisms? - Bacteria, archaea, and eukarya - Bacteria and archaea - Archaea - Eukarya - Bacterial

*Bacteria and archaea

Viruses are characterized by all of the following except - Being capable of independent reproduction - Being acellular - Being found in every organism investigated so far - Being specific to the hosts they infect

*Being capable of independent reproduction

Which of the following is least associated with the others? - Conjugation - Transformation - Horizontal gene transfer - Binary fussion

*Binary fussion

Which statement about slime molds and water molds is incorrect? - Both have flagellated cells at some time in their life cycles - Both are fungi - Both form spores - Both are eukaryotes

*Both are fungi

Amanda is a microbiologist who studies the pathogenic bacteria Streptococcus pyogenes. In what ways are they (Amanda and the bacteria) similar? - Both have linear chromosomes - Both obtain carbon from consuming organic molecules - Both have mitochondria for ATP production - Both are capable of sexual reproduction

*Both obtain carbon from consuming organic molecules

A lytic cycle concludes with the - Production of messenger RNA - Bursting of the host cell - Production of a bacteriophage - Embedding of viral DNA into the host cell's DNA

*Bursting of the host cell

The specific white blood cells that HIV attaches to are the___________ cells . - Gp120-T - CCR5-T - CD4+T - CXCR4-T

*CD4+

A microbiologist is conducting a research project on chemolithoautotrophs. This means that the investigator is examining certain aspects of a bacterium that - Can use the energy from sunlight to build organic molecules from carbon dioxide - Obtains carbon from organic molecules - Is a purple nonsulfur bacteria which depends on light - Can oxidize inorganic molecules such as ammonia and sulfur for energy

*Can oxidize inorganic molecules such as ammonia and sulfur for energy

A viral particle is very simple, consisting of a core of DNA or RNA surrounded by a___________

*Capsid

An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to ____________ - Change the atmosphere from oxidizing to reducing - Prevent the formation of an ozone layer - Make it easier to maintain reduced molecules - Cause iron in ocean water and terrestrial rocks to rust (oxidize) in water

*Cause iron in ocean water and terrestrial rocks to rust (oxidize) in water

While examining a rock surface, you have discovered an interesting new organism. Which of the following criteria will allow you to classify the organism as belonging to Bacteria but not Archaea or Eukarya? - It can survive at a temperature over 100°C - The organism does not have a nucleus - The lipids in its plasma membrane consist of glycerol bonded to straight-chain fatty acids - Cell walls are made primarily of peptidoglycan

*Cell walls are made primarily of peptidoglycan

An autotrophic bacteria that could live in the dark would be a _________________

*Chemoautotroph

Prokaryotes that harvest both energy and carbon atoms from organic molecules are called - Chemoheterotrophs - Chemolithoautotrophs - Photoautotrophs - Photohetrotrophs

*Chemoheterotrophs

Sponges (phylum:Porifera) are animals that possess feeding cells called collar cells. These cells have a central flagellum surrounded by a collar of microvilli. The collar filters organic matter out of the water column. Which protist shares a more recent common ancestor with the poriferans? - Rhodophyta - Radiolarians - Choanoflagellates - Ciliates

*Choanoflagellates

You are given an unknown organism to identify. It is unicellular and heterotrophic. It is motile, using many short extensions of the cytoplasm, each featuring the 9+2 filament pattern. It has well-developed organelles and two nuclei; one large and one small. This organism is most likely to be a _____________ - Radiolarian - Kinetoplastid - Foraminifera - Ciliate

*Ciliate

All ____________ have two very different types of nuclei within their cells, small micronuclei and larger macronuclei. - Ciliates - Protists - Oomycetes - Dinoflagellates

*Ciliates

Vacuoles for ingesting food and regulating their water balance are characteristic of - Ciliates - Algae - Spirochetes - Sporozoans

*Ciliates

Vacuoles for ingesting food and regulating their water balance are characteristic of - Sporozoans - Spirochetes - Ciliates - Algae

*Ciliates

Bacteria trade small sections of plasmid DNA with one another during _________________.

*Conjugation

Which means of genetic recombination in bacteria often make use of pili? - Transduction - Translocation - Conjugation - Transformation

*Conjugation

Retroviruses - Contain the enzyme reverse transcriptase - Only invade plants - Contain DNA - Produce RNA from DNA

*Contain the enzyme reverse transcriptase

Which of the following events or characteristics accounts for someone who has had regular herpesvirus-mediated cold sores or genital sore flare-ups? - Reinfection by the same herpesvirus strain - Copies of the herpesvirus genome permanently maintained in host cell cytoplasm - Reinfection by a closely related herpesvirus of a different strain - Copies of the herpesvirus genome permanently maintained in host nuclei

*Copies of the herpesvirus genome permanently maintained in host nuclei

One hypothesis that has been proposed regarding the origin of life suggests that life evolved from an "RNA world" to today's "DNA world". Considering the properties of RNA and DNA molecules, which questions would direct an investigation of the most insightful test of this hypothesis? - Since ribozymes could freely enter and leave the vesicles, could these molecules have brought external DNA into the cell as a less stable, but more reliable storage molecule of double-stranded DNA? - Could RNA have provided a template for DNA assembly, thereby enabling a more stable molecule that is replicated more accurately? - Is it likely that simple, yet stable RNA molecules served as a primitive precursor to a less stable DNA molecule that was more capable of storing more information? - Is it likely that RNA molecules functioned as ribozymes to synthesize DNA from amino acids, and that this role was reversed when DNA became the information source?

*Could RNA have provided a template for DNA assembly, thereby enabling a more stable molecule that is replicated more accurately?

The group that probably gave rise to chloroplast is the - Purple sulfur bacteria - Green photosynthetic bacteria - Nonsulfur purple bacteria - Cyanobacteria

*Cyanobacteria

Organisms that are characterized by being unicellular, photosynthetic, and having double shells made of silica are known as - Foraminifera - Kelp - Dinoflagellates - Diatoms

*Diatoms

If a fossil is encased in a stratum of sedimentary rock any of volcanic rock (for example, lava or ash) nearby, then it should be ____________ - Difficult to determine the absolute age of the fossil, because radiometric dating of sedimentary rock is less accurate than that of igneous rock - Easy to determine the absolute age of the fossil, because the igneous rocks will not have physically obstructed the deposition of sediment of a single age next to the fossil - Easy to determine the absolute age of the fossil, because the radioisotopes in the sediments will not have been "reset" by the heat of the igneous rocks - Difficult to determine the absolute age of the fossil, because the "marker fossils" common to igneous rock will be absent

*Difficult to determine the absolute age of the fossil, because radiometric dating of sedimentary rock is less accurate than that of igneous rock

Some protist cell surfaces have __________, including silica or calcium carbonate

*ECM

Nearly all viruses are constructed of - RNA with a protein wrapping, called a capsid. - Either DNA or RNA, however many do not have the capsid - Either DNA or RNA with a protein wrapping, called a capsid - DNA with a protein wrapping, called a capsid

*Either DNA or RNA with a protein wrapping, called a capsid

When bacteria are exposed to nutrient-poor conditions, they form thick walled structures that contain the chromosome and a small amount of cytoplasm. These structures are called - Endospores - Nucleoids - Plasmids - Exospores

*Endospores

Eukaryotic cells acquired mitochondria and chloroplasts by - Natural selection - Endosymbiosis - Pinocytosis - Exocytosis

*Endosymbiosis

Which of the following is not a characteristic of Paramecium? - A micronucleus functions in reproduction - Engulfs prey with pseudopods - A macronucleus produces mRNA and directs metabolic functions - Motile with cilia

*Engulfs prey with pseudopods

Viruses cause infection by - Forming endospores in the body - Producing toxins that harm the body - Reproducing independently inside the body - Entering body cells and reproducing

*Entering body cells and reproducing

A layer of lipoprotein and glycoprotein that covers the outer surface of some viruses is the - Envelope - Membrane - Casing - Capsid

*Envelope

Outside the protein sheath, many viruses have a(n) ______________ made of protein, lipid, and carbohydrate

*Envelope

All protists are _____________. - Symbionts - Mixotrophic - Eukaryotic - Unicellular

*Eukaryotic

All bacteria have the same shape - True - False

*False

Bacteria can reproduce by dividing in two, called transformation - True - False

*False

Bacteria typically use binary fission, but under special circumstances sexuai reproduction is possible via horizontal gene transfer - True - False

*False

Bacteria, protists, and fungi belong to the domain Archaea. -True -False

*False

Protists are a diverse group of mainly multicellular eukaryotes - True - False

*False

Protists are part of the domain Bacteria - True - False

*False

RNA was probably the first molecule used to encode genetic information; the use of DNA came later. This is due to RNA's inherent stability and its ability to store information more accurately than DNA

*False

Retroviruses are unique because they are a combination of RNA and DNA. - True - False

*False

The pneumonia caused by the influenza virus results from the accumulation of fluid and cell debris in the lungs. This occurs during the lysogenic life cycle of the virus - True - False

*False

The pneumonia caused by the influenza virus results from the accumulation of fluid and cell debris in the lungs. This occurs during the lysogenic life cycle of the virus. - True - False

*False

Which of these mismatched? - Kuru-prion - Food poisoning-archaea - Tetanus-bacterium - AIDS-virus

*Food poisoning-archaea

The White Cliffs of Dover, a famous landmark in England, is made of limestone, which is really a collection of the pore-studded shells (tests) of - Brown algae - Forminifera - Diatoms - Dinoflagellates

*Forminifera

In some bacteria, a capsule surrounds the cell wall. It is made up of - Pili - Opeptidoglycan - Glycoprotein - Gelatin

*Gelatin

Prokaryotes reproduce rapidly and this allows genetic variation to spread quickly through a population. Two processes can create new variations in prokaryotic populations. Select the choice with those two processes. - Genetic recombination and mutation - Mutation and phage viral attack - Genetic recombination and nondisjunction - Genetic recombination and rapid cell division

*Genetic recombination and mutation

Which of the following processes can be effective in preventing the onset of viral infection in humans? - Taking vitamins before being exposed to various viruses - Getting vaccinated to certain viruses - Taking antibiotics to inhibit bacterial growth - Taking drugs that inhibit transcription

*Getting vaccinated to certain viruses

How was early Earth from more than three billion years ago different from today's Earth? Unlike Earth today, early Earth _____________ - Had an oxidizing atmosphere - Had an atmosphere rich in gases released from volcanic eruptions - Had an atmosphere with significant quantities of ozone - Experienced little high-energy radiation from the sun

*Had an atmosphere rich in gases released from volcanic eruptions

One way in which retroviruses differ from all other types of viruses is that retroviruses - Have the enzyme reverse transcriptase - Have single-strained RNA that serves as viral mRNA - Possess only single-stranded nucleic acids - Can create a prophage

*Have the enzyme reverse transcriptase

A scientist is studying endosymbiosis in cells . This means she is investigating - How mitochondria and chloroplasts evolved into prokaryotic cells - How mitochondria and chloroplasts were derived from prokaryotic cells - How mitochondria and chloroplasts were derived from eukaryotic cells - How mitochondria and chloroplasts evolved into eukaryotic cells

*How mitochondria and chloroplasts were derived from prokaryotic cells

Which of the following characteristics are expected in the first animals to have colonized land? - I.) They were probably herbivores (ate photosynthesizers) - II.) Animals had four appendages - III.) Animals had the ability to resist dehydration - IV.) Animals had lobe-finned fishes as ancestors - V.) Invertebrates

*I , III and V

Which of the following is the correct sequence of events in the origin of life? 1. Formation of protocells 2. Synthesis of organic monomers 3. Synthesis of organic polymers 4. Formation of DNA-based genetic systems - I , III , II , IV - II , III , IV , I - II , III , I , IV - I , II , III , IV

*II , III , I , IV

Which of the following is not a shape seen in prokaryotes? - Rods - Spheres - Icosahedrals - Spirals

*Icosahedrals

What adaptions by mammals helped their adaptive radiation after extinction of terrestrial dinosaurs? - Increase in diversity - Nocturnal vision - Outcompeting for food - Small size

*Increase in diversity

An experimental test of the hypothesis to explain the origin of the first organic compounds on Earth might include all of the following sequental steps except - Providing energy with electrical spark discharges - Inoculating with a few bacteria to get the process started - Placing this atmosphere over liquid water - Assembling an atmosphere with H2 , CH4 , NH3 , and H2S .

*Inoculating with a few bacteria to get the process started

Which of these occurs during the bacteriophage lysogenic cycle but not the lytic cycle? - Maturation - Attachment - Integration - Penetration

*Integration

An individual mixotroph loses its plastids, yet continues to survive. Which of the following most likely accounts for its continued survival? - It engulfs organic material by phagocytosis or by absorption - It relies on photosystems that float freely in its cytosol - It has an endospore - It must have gained extra mitochondria when it lost its plastids

*It engulfs organic material by phagocytosis or by absorption

If a virus enters the lytic phase in a host's cell, it will cause cell to - Shrink because of the loss of cytoplasm that has been used in the synthesis of viral DNA - Replicate itself at a higher than normal frequency - Reject the virus - Lyse due to the action of enzymes

*Lyse due to the action of enzymes

A researcher infects a bacterium with a bacteriophage and notices that the infection does not immediately bring about the destruction of the host cell. Instead, the phage's genetic material is copied whenever the host reproduces. Which viral replication cycle is described here? - Lysogenic cycle - Integration cycle - Lytic cycle - Biosynthetic cycle

*Lysogenic cycle

Which of the statements is true about dinoflagellates? - They have shoebox-shaped cell walls of silica - They contain bright yellow pigments - They can be both photosynthetic and heterotrophic - Many species are luminescent

*Many species are luminescent

Which of the following does not provide support for the endosymbiotic hypothesis? - Mitochondria and chloroplasts contribute to different metabolic processes in the eukaryotic cell - Mitochondria and chloroplasts contain genes that are strikingly similar to bacterial genes - Mitochondria and chloroplasts have their own genomes - Double membranes are around mitochondria and chloroplasts

*Mitochondria and chloroplasts contribute to different metabolic processes in the eukaryotic cell

Which of the following statements would not be consistent with the theory for the endosymbiotic origin of mitochondria and chloroplasts? - Mitochondria and chloroplasts have some enzymes unique to them - Mitochondria and chloroplasts have their own DNA enclosed within a nuclear envelope - The composition of the inner membrane of chloroplasts and mitochondria is similar to the plasma membrane of prokaryotic cells - The composition of the outer membrane of chloroplasts and mitochondria is similar to the plasma membrane of eukaryotic cells

*Mitochondria and chloroplasts have their own DNA enclosed within a nuclear envelope

Two principal organelles in eukaryotes that were apparently derived from different types of bacteria are the - Plasma membrane and nuclear membrane - Microfilaments and microtubules - Mitochondria and chloroplasts - Rough ER and smooth ER .

*Mitochondria and chloroplasts.

Some photosynthetic euglenoids can also ingest dissolved or particulate food. Which one of the following terms would best describe such a protist? - Phagotrophic - Mixotrophic - Heterotrophic - Autotrophic

*Mixotrophic

A doctor's office has run out of the latest flu vaccine, but many patients are asking for it. One of the nurses finds some vials from last year's batch in a refrigerator. Should they be used? - Maybe the vaccine should be mixed in a test tube with the virus to see if it still inactivates it. - No, because each year the vaccine is made against different subtypes of the flu virus. - No, because each year the technology to make a good vaccine improves. - Yes, because the preservatives and refrigeration ensure that the vaccine is still fresh.

*No, because each year the vaccine is made against different subtypes of the flu virus.

Can a virus be killed? - No, viruses are capable of self-assembly and cannot be permanently killed - Yes, destroying its genome kills it - Yes, separating the genes from the capsid kills it - No, viruses are nonliving and cannot die

*No, viruses are nonliving and cannot die

Are transformation and transduction the same process? - Yes; both processes transfer specific gene products to a specific bacterium - Yes; they both involve the acquisition of viral genes - No; only transformation passes on genes for pathogenicity - No; although both involve gene transfer the sources of the genetic material differ

*No; although both involve gene transfer the sources of the genetic material differ

Will treating a viral infection with antibiotics affect the course of the infection? - No; antibiotics work by inhibiting enzymes specific to bacteria. Antibiotics have no effect on eukaryotic or virally encoded enzymes - Yes; antibiotics activate the immune system, and this decreases the severity the infection - Yes; antibiotics can prevent viral entry into the cell by binding to host-receptor proteins - No; antibiotics do not kill viruses because viruses do not have DNA or RNA

*No; antibiotics work by inhibiting enzymes specific to bacteria. Antibiotics have no effect on eukaryotic or virally encoded enzymes

In addition to their characteristic cilia, most ciliates contain two types of - Chloroplasts - Flagella - Nuclei - Cysts

*Nuclei

In all of the following characteristics, prokaryctes differ from eukaryotes except in - Cell size - Chromosomes - Multicellularity - Nucleic acids as the hereditary material

*Nucleic acids as the hereditary material

The prokaryotic DNA is located in the - Nucleoid region - Capsid region - Peptidoglycan region - Endospore region

*Nucleoid region

Cell walls of bacteria (domain Bacteria) usually consist of______________, a network of polysaccharide molecules connected by polypeptide cross-links.

*Peptidoglycan

A bacterium is found that can photosynthesize in the presence of light but uses hydrogen sulfide and releases elemental sulfur as a by-product. This organism can best be classified as a - Pathogen - Chemoheterotroph - Photoheterotroph - Photoautotroph

*Photoheterotroph

Some prokaryotes attach to other substrates by hairlike outgrowths, which are shorter than flagella. These are called - Flagellin - Endospores - Plasmids - Pili

*Pili

Which of the following events is least likely to result in a genetic change in a bacterium? - Conjugation - Specialized transduction - Pilus formation - Generalized transduction

*Pilus formation

In a bacterium that possesses antibiotic resistance and the potential to persist through very adverse conditions, such as freezing, drying, or high temperatures, DNA should be located within, or be part of, which structures? - Fimbriae, nucleoid, and endospore - Endospore, fimbriae, and plasmids - Nucleoid, fimbriae, and plasmids - Plasmids, nucleoid, and endospore

*Plasmids, nucleoid, and endospore

Which phrase best describes the characteristics of plasmodium? - Plasmodial slime molds consist of large multinucleate single cells - Plasmodial slime molds consist of large single nucleate cells - Plasmodial slime molds are multicellular - Plasmodium cells contain a pellicle

*Plasmodial slime molds consist of large multinucleate single cells

Dinoflagellates _________________ - Include species that cause malaria - Possess two flagella - Are all autotrophic - Lack mitochondria

*Possess two flagella

A virus's DNA or RNA is surrounded by a(n) - Nuclear membrane - Endospore - Tail - Protein coat

*Protein coat

Most viruses form a capsid around their nucleic acid core. This capsid is composed of - Monosaccharides - Proteins - Glycoproteins - Lipoproteins

*Proteins

Eukaryotes that are not plants, animals, or fungi are considered ________________.

*Protists

Cell-like structures that may have resulted from macromolecular self assembly are referred to as - Prokaryotes - Protoypes - Archaea - Protocells

*Protocells

The single-celled protists are often mobile and use a variety of propulsive mechanisms, for example, the amoeba move by means of - Flagella - Coccoliths - Pseudopodia - Cilia

*Pseudopodia

Amoebas move from place to place by means of their - Pseudomonads - Pseudopods - Cysts - Sporocarps

*Pseudopods

Which of the following is not thought to have contributed to the many mass extinction events that have occurred throughout Earth's history? - Habitat loss - Punctuated equilibrium - Meteorite impacts - Plate tectonics

*Punctuated equilibrium

In addition to the true amoebas (Rhizopoda), another group with pseudopods are the - Stramenopila - Alveolata - Radariolarians - Euglenozoa

*Radariolarians

What is the most accurate method used to measure the age of a fossil? - Use uranium-238 - Sequence fossils in rock strata - Use whole-life decay - Radiometric dating

*Radiometric dating

Which group of algae will have calcium carbonate within their cell walls? - Diatoms - Green algae - Brown algae - Red algae

*Red algae

Viruses can_____________ only after they have entered a host cell , and only by using the host's cellular machinery.

*Replicate

Fossilized stromatolites - Formed around deep-sea vents - Provide evidence that plants moved onto land in the company of fungi around 500 million years ago - Contain the first undisputed fossils of eukaryotes - Resemble structures formed by bacterial communities that are found today in some shallow marine bays

*Resemble structures formed by bacterial communities that are found today in some shallow marine bays

A virus consisting of a single strand of RNA, which is reverse transcribed into complementary DNA, is referred to as a ___________. - Non-enveloped virus - Retrovirus - Bacteriophage - Protease

*Retrovirus

The first genetic material on Earth was probably __________ - Oligopeptides located within protocells - DNA molecules whose information was transcribed to RNA and later translated in polypeptides - DNA produced by reverse transcriptase from abiotically produced RNA and - Self-replicating RNA molecules

*Self-replicating RNA molecules

Current classification of prokaryotes is based on - Type of colony formation - Occurrence of transverse binary fission - Sequencing of proteins, DNA, and RNA - Morphology of flagella

*Sequencing of proteins, DNA, and RNA

The unique double shells of diatoms are made of - Chlorophyll - Cellulose - Agar - Silica

*Silica

One group of protozoans which are nonmotile, produce spores, and have disease-causing species is the - Sporozoans - Trypanosomes - Foraminiferans - Amoeboids

*Sporozoans

The first class of antiviral drugs developed to treat HIV infection, such as AZT, were known as reverse transcriptase inhibitors. How did these drugs carry out their functions? - The drug molecules bonded to the dsDNA genome of the virus in such a way that it could not separate for replication to occur - The drugs targeted and destroyed the viral genome before it could be reverse transcribed into DNA - The drug molecules bonded to the viral reverse transcriptase enzyme, thus preventing the virus from making a DNA copy of its RNA genome - The drugs prevented host cells from producing the enzymes used by the virus to replicate its genome

*The drug molecules bonded to the viral reverse transcriptase enzyme, thus preventing the virus from making a DNA copy of its RNA genome

The oxygen revolution changed Earth's environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere? - The evolution of photosynthetic pigments that protected early algae from the corrosive effects of oxygen - The evolution of chloroplasts after early protists incorporated photosynthetic cyanobacteria - The evolution of cellular respiration , which used oxygen to help harvest energy from organic molecules - The persistence of some animal groups in anaerobic habitats

*The evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules

Why are fossils considered to be an incomplete record of evolution? - The fossil record is biased for organisms that had hard shells and skeletons - The fossil record shows changes in kinds of organisms that lived on earth - The fossil record shows that many animals are extinct - Fossils document how new organisms come from preexisting organisms

*The fossil record is biased for organisms that had hard shells and skeletons

What criteria best characterize membership in the kingdom Protista? - A large assortment of unique shared derived trait - The inability to meet the characteristics that define each of the remaining eukaryotic kingdoms - A common evolutionary heritage - A continuous lineage of descent from a common ancestor

*The inability to meet the characteristics that define each of the remaining eukaryotic kingdoms

A student outlined the following steps of the lytic cycle of bacteriophage infection of bacterial cells: 1. Virus lands on host cell 2. Virus injects the capsid containing its DNA into the cell 3. Viral DNA is used by bacteria to make virus parts 4. New viruses are assembled in the bacterial cell What step should the student add as # 5 in the outline? - The new viruses release their DNA - The virus becomes a part of the bacteria - The new viruses break out of the cell - The bacterial cell divides

*The new viruses break out of the cell

Which feature unites paramecia, malarial parasites, and dinoflagellates into a single group? - The possession of alveoli - The use of cilia - The presence of a nucleus - The type of ribosomes

*The possession of alveoli

What would be strong evidence to suggest a protist is phototrophic? - The presence of chloroplasts - Locomotion via several flagella - A benthic lifestyle - Many lysosomes

*The presence of chloroplasts

The host range of a virus is determined by _____________ - Whether its nucleic acid is DNA or RNA - The proteins in the host's cytoplasm - The enzymes-carried by the virus - The proteins on its surface and that of the host

*The proteins on its surface and that of the host

If all prokaryotes on Earth suddenly vanished, which of the following would be the most likely and most direct result? - The recycling of nutrients would be greatly reduced, at least initially - There would be no more pathogens on Earth - Bacteriophage numbers would dramatically increase - Human populations would thrive in the absence of disease

*The recycling of nutrients would be greatly reduced, at least initially

Why don't new biological macromolecules form abiotically from nonliving matter on the Earth today? - There are not enough of the various elements needed - The special environmental conditions that are required do not exist - There is no need for biological macromolecules - There is not enough available energy .

*The special environmental conditions that are required do not exist .

A student outlined the following steps of the lytic cycle of bacteriophage infection of bacterial cells: 1. Virus lands on host cell 2. Virus injects the capsid containing its DNA into the cell 3. Viral DNA is used by bacteria to make virus parts 4. New viruses are assembled in the bacterial cell Which step would the student need to add to describe a lysogenic cycle? - The bacterial wall fuses with the capsid - The bacterial DNA is replaced by the viral DNA - The viral proteins are used to make new viruses - The viral DNA becomes a part of the bacterial DNA

*The viral DNA becomes a part of the bacterial DNA

Once a prophage is present in a bacterial genome, viral genes are reproduced every time the bacterium multiplies. Expression of viral genes, however, is inhibited by a repressor protein. Cell stress can induce the formation of proteases that degrade the repressor. What will result? - The bacterial genome will be denatured - The bacterium will reject the viral genes - The virus will enter the lytic cycle - The virus will enter the lysogenic cycle

*The virus will enter the lytic cycle

Biologists sometimes divide living organisms into two groups: autotrophs and heterotrophs. These two groups differ in _________________. - The way that they generate ATP - Their sources of carbon - Their electron acceptors - Their mode of inheritance

*Their sources of carbon

What is true of the Cambrian explosion? - The Cambrian explosion is evidence for the instantaneous creation of life on Earth - The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record - Only the fossils of microorganisms are found in geological strata older than the Cambrian explosion - There are fossils of animals in geological strata that are older than the Cambrian explosion

*There are fossils of animals in geological strata that are older than the Cambrian explosion

Protists are classified into a single kingdom because of which of the following features? - All types of nutritional modes are found - They are microscopic - They are unicellular - They are eukaryotes, but not fungi, plants, or animals

*They are eukaryotes, but not fungi, plants, or animals

Which of the following is characteristic of ciliates? - Most live as solitary autotrophs in fresh water - They use pseudopods as feeding structures - They are often multinucleate - They can exchange genetic material with other ciliates by the process of mitosis

*They are often multinucleate

Which of the following processes can viruses carry out? - They can use the host cell to copy themselves and then synthesize their own proteins inside the viral capsid. - They can metabolize food and produce their own ATP. - They can use the host cell to copy themselves and make viral proteins. - They can manufacture their own ATP, proteins, and nucleic acids .

*They can use the host cell to copy themselves and make viral proteins.

Which of the following statements supports the argument that viruses are nonliving? - They do not evolve - They do not carry out metabolic processes - They have RNA rather than DNA - Their DNA does not encode proteins

*They do not carry out metabolic processes

Which of the following is not one of the distinctive features of dinoflagellates? - They are photosynthetic - They form large, spherical colonies - They are unicellular - Some planktonic members are luminous and cause flashes in the night

*They form large, spherical colonies

Which of the following characteristics correctly describes retroviruses? - They have a single-stranded DNA that acts as a template for DNA synthesis - They have a single-stranded RNA that acts as a template for DNA synthesis - They can only reproduce by infecting bacteria - They are made up of only a single protein

*They have a single-stranded RNA that acts as a template for DNA synthesis

Which of the following statements is NOT true about archaebacteria? - Many live in harsh environments - They are thought to be ancestors of eukaryotes - They lack peptidoglycan in their cell wall - They make up the largest kingdom of prokaryotes

*They make up the largest kingdom of prokaryotes

How do humans use red algae polysaccharides? - Herbicides - Adhesives - Thickeners - Detergents

*Thickeners

Which of the following describe all existing bacteria? - Pathogenic, omnipresent, morphologically diverse - Extremophiles, tiny, abundant - Morphologically diverse, metabolically diverse, extremophiles - Extremophiles, tiny, abundant - Tiny, ubiquitous, metabolically diverse

*Tiny, ubiquitous, metabolically diverse

What is the goal of bioremediation? - To improve soil quality for plant growth by using bacteria - To improve bacteria for production of useful chemicals - To clean up areas polluted with toxic compounds by using bacteria - To improve human health with the help of living organisms such as bacteria

*To clean up areas polluted with toxic compounds by using bacteria

A population explosion of dinoflagellates can cause a red tide - True - False

*True

Archaea, Bacteria, and Eukarya are the three biological domains - True - False

*True

The influenza virus evolves rapidly because DNA changes are frequently incorporated into the virus as it is being made. - True - False

*True

The kingdom Bacteria consists of the same species as the domain Bacteria - True - False

*True

Which of the following statements correctly describes vaccines and how they help prevent viral infection? - Vaccines are infectious enzymes that stimulate an immune reaction in a person - Vaccines are active versions of a virus that stimulate an immune reaction in a person - Vaccines are infectious proteins that stimulate an immune reaction in a person - Vaccines are inactive versions of a virus that stimulate an immune reaction in a person

*Vaccines are inactive versions of a virus that stimulate an immune reaction in a person

A ___________ can contain DNA or RNA as its genetic material, but not both

*Virus

Which of the following statements is not true of all viruses? - Viruses have an inner core of nucleic acid - Viruses have a protein capsid - Viruses are obligate intracellular parasites - Viruses have envelopes

*Viruses have envelopes

Which of the following groups contains no photosynthetic organisms? - Archaea - Zooflagellates - Prokaryotes - Bacteria

*Zooflagellates

Protists may superficially resemble organisms in the other kingdoms; one exception is the kingdom ______________, whose members do not resemble protists in any meaningful way - Bacteria - Fungi - Plantae - Animalia

Bacteria

Virulent viruses multiply within infected cells and eventually - Cause the transformation of the host cell , releasing new viruses - Cause lysis of the host cell, releasing new viruses - Cause an alternation of generations in the host cell, releasing new viruses - Cause the transduction of the host cell , releasing new viruses

Cause lysis of the host cell, releasing new viruses

Spherical prokaryotes are called - Cocci - Bacilli - Flagella - Spirtla

Cocci

Juanita caught a cold because viruses were able to bind to capsules on her cells. - True - False

False

________infects the CD4+T cells, which are required for normal immunity.

HIV