Biology Test

Based on the data in the Amino Acid Identity Table, which two members of the human globin gene family are the most divergent?

? and ß

Which of the following sequences is most likely to be cut by a restriction enzyme?

AATATT TTATAA

Which of the following human diseases is caused by a virus that requires reverse transcriptase to transcribe its genome inside the host cell?

AIDS

Which of the following 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.

What is difference between an epidemic and a pandemic?

An epidemic is restricted to a local region; a pandemic is global.

Reproductive cloning of human embryos is generally considered unethical. However, on the subject of therapeutic cloning there is a wider divergence of opinion. Which of the following is a likely explanation?

Cloning to produce embryonic stem cells may lead to great medical benefits for many.

A sequence database such as GenBank could be used to do all of the following EXCEPT

Compare patterns of gene expression in cancerous and non-cancerous cells.

Which of the following techniques would be most appropriate to test the hypothesis that humans and chimps differ in the expression of a large set of shared genes?

DNA microarray analysis

What is the function of reverse transcriptase in retroviruses?

It uses viral RNA as a template for DNA synthesis.

Studies in knockout mice have demonstrated an important role of the FOXP2 transcription factor in the development of vocalizations. Recent sequence comparisons of the FOXP2 gene in Neanderthals and modern humans show that while the DNA sequence may be different, the protein sequence it codes for is identical. What might logically be inferred from this information?

Human and Neanderthal vocalizations may have been more similar than previously thought.

Which of the following is a representation of gene density?

Humans have ~20,000 protein-encoding genes in 2900 Mb.

What is the main structural difference between enveloped and nonenveloped viruses?

Enveloped viruses have a phospholipid membrane outside their capsid, whereas nonenveloped viruses do not have a phospholipid membrane.

Organisms share many conserved core processes and features, including transcription and translation using a uniform genetic code. Scientists have used these shared processes and features in biotechnology. For example, for the process of some transformations, a plasmid is constructed when a eukaryotic gene of interest is added with an antibiotic resistant gene such beta-lactamase, which is used for ampicillin resistance. This plasmid is then inserted into a prokaryotic bacterial cell, such as E-coli, through a transformation process that leads to the production of the product protein from the eukaryotic organism. To culture the bacteria and obtain the protein product, the bacteria must grow. Select the appropriate condition to determine if the plasmid has entered the E-coli bacterial cell.

Nutrient broth to which ampicillin has been added.

Why do RNA viruses appear to have higher rates of mutation?

Replication of their genomes does not involve proofreading.

In large scale, genome-wide association studies in humans we look for _____.

SNPs where one allele is found more often in persons with a particular disorder than in healthy controls

A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding?

The cells from the two sources exhibit different patterns of DNA methylation.

A microarray is a tool used in genetic research to determine the mRNAs being produced in a particular tissue, and their relative level of expression. Known genes can therefore be assayed for their expression in different situations. One use of the technology is in cancer diagnosis and treatment. If a known gene functions as a tumor suppressor, predict which of the following pieces of evidence would be most useful in diagnosis of a cancer due to a mutation in this tumor- suppressor gene.

The mRNAs for the targeted tumor suppressor sequence are not being produced.

Which of the following represents a difference between viruses and viroids?

Viruses have capsids composed of protein, whereas viroids have no capsids.

The first cloned cat, called Carbon Copy, was a calico, but she looked significantly different from her female parent because _____.

X inactivation in the embryo is random and produces different patterns

Which of the following supports the argument that viruses are nonliving?

They are not cellular.

Which of the following is true of embryonic stem cells but not of adult stem cells?

They can give rise to all cell types in the organism.

Which of the following is one of the technical reasons why gene therapy is problematic?

Transferred genes may not have appropriately controlled activity.

A principal problem with inserting an unmodified mammalian gene into a plasmid and then getting that gene expressed in bacteria is that _____.

bacteria cannot remove eukaryotic introns

When gene duplication occurs to its ultimate extent by doubling all genes in a genome, what has occurred?

creation of a polyploid

The figure above shows a diagram of blocks of genes on human chromosome 16 and the locations of blocks of similar genes on four chromosomes of the mouse. The movement of these blocks suggests that _____.

chromosomal translocations have moved blocks of sequences to other chromosomes

If the sequence of a cDNA has matches with DNA sequences in the genome, then this genomic DNA is likely to _____.

code for a protein

Using modern techniques of sequencing by synthesis and the shotgun approach, sequences are assembled into chromosomes by ______.

computer analysis looking for sequence overlaps.

Imagine that you compare two DNA sequences found in the same location on homologous chromosomes. On one of the homologs, the sequence is AACTACGA. On the other homolog, the sequence is AACTTCGA. Within a population, you discover that each of these sequences is common. These sequences _____.

contain an SNP that may be useful for genetic mapping

In many ways, the regulation of the genes of a particular group of viruses will be similar to the regulation of the host genes. Therefore, which of the following would you expect of the genes of a bacteriophage?

control of more than one gene in an operon

For a particular microarray assay (DNA chip), cDNA has been made from the mRNAs of a dozen patients' breast tumor biopsies. The researchers will be looking for _____.

a pattern shared among some or all of the samples that indicates gene expression differing from control samples

Mutations that occur in one member of a gene pair that arose from gene duplication may create _____.

a pseudogene, a gene with a new function, and a gene family with two distinct but related members

card image Which enzyme was used to produce the molecule in the figure above?

a restriction enzyme (endonuclease)

Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because _____.

a sequence that is found to have a particular function in the nematode is likely to have a closely related function in vertebrates

Bacterial cells protect their own DNA from restriction enzymes (endonucleases) by _____.

adding methyl groups to adenines and cytosines

DNA microarrays have made a huge impact on genomic studies because they _____.

allow the expression of many or even all of the genes in the genome to be compared at once

In the form of gene therapy used successfully for severe combined immunodeficiency syndrome (SCID)-X1, the genetic engineering of human cells is done by _____.

isolating the patient's bone marrow cells, infecting them with genetically engineered viruses, and injecting them back into the patient's bone marrow

A DNA microarray is a tool that owes its existence to earlier genomics investigations. What essential contribution of genomics makes microarrays possible?

knowledge of which DNA sequences to synthesize for the array

Sequencing eukaryotic genomes is more difficult than sequencing genomes of bacteria or archaea because of the _____.

large size of eukaryotic genomes and the large amount of eukaryotic repetitive DNA

Several of the different globin genes are expressed in humans, but at different times in development. What mechanism could allow for this?

differential gene regulation over time

What is gene annotation in bioinformatics?

finding transcriptional start and stop sites, RNA splice sites, and ESTs in DNA sequences

In 1997, Dolly the sheep was cloned. Which of the following processes was used?

fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate

A multigene family is composed of _____.

genes whose sequences are very similar and that probably arose by duplication

Which of the following can be effective in preventing the onset of viral infection in humans?

getting vaccinated

What information is critical to the success of polymerase chain reaction (PCR) itself?

he DNA sequence of the ends of the DNA to be amplified must be known.

Genetically engineered plants _____.

include transgenic rice plants that can grow in water of high salinity

Using retroviral vectors for gene therapy might increase the patient's risk of developing cancer because they might _____.

integrate recombinant DNA into the genome in ways that misregulate the expression of genes at or near the site of integration

Effective antiviral drugs are usually associated with which of the following properties?

interference with viral replication

Which of the following is most like the formation of identical twins?

organismal cloning

One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome?

prevention of transmission of plant allergens to the vaccine recipients

A researcher has used in vitro mutagenesis to mutate a cloned gene and then has reinserted the mutated gene into a cell. To have the mutated sequence disable the function of the gene, what must then occur?

recombination resulting in replacement of the wild type with the mutated gene

a current view of how the human and chimpanzee can share most of their nucleotide sequence yet exhibit significant phenotypic differences is that many of the most important sequence differences alter _____.

regulatory sequences

Which viruses have single-stranded RNA that acts as a template for DNA synthesis?

retroviruses

A laboratory might use dideoxyribonucleotides to _____.

sequence a DNA fragment

What is metagenomics?

sequencing DNA from a group of species from the same ecosystem

Exon shuffling occurs during _____.

meiotic recombination

The virus genome and viral proteins are assembled into virions (virus particles) during _____.

the lytic cycle only

The comparison between the number of human genes and those of other animal species has led to many conclusions, including that _____.

the number of proteins expressed by the human genome is far more than the number of its genes

The host range of a virus is determined by _____.

the proteins on its surface and that of the host

Although transposable elements and short tandem repeats (STRs) are repetitive DNAs, they differ in that _____.

the repeated unit in STRs is clustered one after another; transposable element repeats are scattered throughout the genome

What can proteomics reveal that genomics cannot?

the set of proteins present within a cell or tissue type

RNAi methodology uses double-stranded pieces of RNA to trigger breakdown of a specific mRNA or inhibit its translation. For which of the following might this technique be useful?

to decrease the production from a harmful mutated gene

Why is it so important to be able to amplify DNA fragments when studying genes?

A gene may represent only a millionth of the cell's DNA.

Which of the following is characteristic of the lytic cycle?

A large number of phages are released at a time.

In recent times, it has been shown that adult cells can be induced to become pluripotent stem cells (iPS). To make this conversion, what has been done to the adult cells?

A retrovirus is used to introduce four specific regulatory genes.

current analysis indicates that less than 2% of the human genome codes for proteins. Based on the systems approach employed by the ENCODE project, what percentage of the genome is estimated to contain functional elements (includes functional RNAs and regulatory sequences)?

At least 80%

Plasmids are used as vectors in plant and bacterial genetic engineering. However, there is a major difference in the fate of genes introduced into bacteria on most bacterial plasmids and into plants on tumor-inducing (Ti) plasmids. What is this difference?

Bacterial plasmids and the genes they carry usually are not integrated into the chromosome; Ti plasmids and the genes they carry are integrated into the chromosome.

In what sense are studies by nineteenth-century naturalists and those by early twenty-first- century genomic biologists similar?

Both focused on observing and describing what exists in their realms of investigation.

Why might the cricket genome have eleven times as many base pairs as that of Drosophila melanogaster?

Crickets must have more noncoding DNA.

For applications in gene therapy, what is the most favorable characteristic of retroviruses?

DNA copies of retroviral genomes become integrated into the genome of the infected cell.

Which of the following can be duplicated in a genome?

DNA sequences, chromosomes, or sets of chromosomes

Which of the following is in the correct order for one cycle of polymerase chain reaction (PCR)?

Denature DNA; anneal primers; extend primers.

One predicted aspect of climate change is that climates, including precipitation and temperature, over most of the Earth will become more variable. Which of the following is a good crop genetic engineering strategy if this is true?

Genetically engineer several genotypes within single crop types.

Why do scientists consider HIV to be an emerging virus?

HIV suddenly became apparent and widespread in the 1980s.

Which of the following processes within viral replication is the greatest source of genetic variation in RNA virus populations?

High mutation rate due to lack of proofreading of RNA genome replication errors.

Let us suppose that someone is successful at producing induced pluripotent stem cells (iPS) for replacement of pancreatic insulin-producing cells for people with type 1 diabetes. Which of the following could still be problems? I. the possibility that, once introduced into the patient, the iPS cells produce nonpancreatic cells II. thefailureoftheiPScellstotakeupresidenceinthepancreas III. the inability of the iPS cells to respond to appropriate regulatory signals

I, II, and III

Bioinformatics includes _____. I. using computer programs to align DNA sequences II. creating recombinant DNA from separate species III. developing computer-based tools for genome analysis IV. using mathematical tools to make sense of biological systems

I, III, and IV

You isolate an infectious substance capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal to analyze the substance and determine the nature of the infectious agent. I. Treat the substance with enzymes that destroy all nucleic acids and then determine whether the substance is still infectious. II. Filterthesubstancetoremoveallelementssmallerthanwhatcanbeeasilyseenunderalight microscope. III. Culture the substance on nutritive medium, away from any plant cells. IV. Treat the sample with proteases that digest all proteins and then determining whether the substance is still infectious. If you already know that the infectious agent was either bacterial or viral, which method(s) listed above would allow you to distinguish between these two possibilities?

II or III

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium? I. Transform bacteria with a recombinant DNA molecule. II. Cut the plasmid DNA using restriction enzymes (endonucleases). III. Extract plasmid DNA from bacterial cells. IV.Hydrogen-bond the plasmid DNA to nonplasmid DNA fragments. V. Use ligase to seal plasmid DNA to nonplasmid DNA.

III, II, IV, V, I

DNA sequencing has transformed our understanding of genes, genomes and evolution. Which of the following statements comparing two common sequencing techniques, the chain termination method and next generation sequencing is TRUE?

In the chain termination method, the order of bases is detected by fluorescently labeling each dideoxy-nucleotide in a different color, while next generation sequencing determines the order of bases by detecting the release of PPi during the formation of the phosphodiester bond.

Silencing of selected genes is often done using RNA interference (RNAi). Which of the following questions would NOT be answered with this process?

Is gene HA292 expressed in individuals for a disorder in humans?

Scientists developed a set of guidelines to address the safety of DNA technology. Which of the following is one of the adopted safety measures?

Microorganisms used in recombinant DNA experiments are genetically crippled to ensure that they cannot survive outside of the laboratory.

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.

Pax-6 is a gene that is involved in eye formation in many invertebrates, such as Drosophila. Pax-6 is also found in vertebrates. A Pax-6 gene from a mouse can be expressed in a fly and the protein (PAX-6) leads to a compound fly eye. This information suggests which of the following?

Pax-6 is highly conserved and shows shared evolutionary ancestry.

In 2009, a flu pandemic was believed to have originated when viral transmission occurred from pig to human, thereby earning the designation, "swine flu." Although pigs are thought to have been the breeding ground for the 2009 virus, sequences from bird, pig, and human viruses were all found within this newly identified virus. What is the most likely explanation of why this virus contained sequences from bird, pig, and human viruses?

Related viruses can undergo genetic recombination if the RNA genomes mix and match during viral assembly.

Poliovirus is an RNA virus of the picornavirus group, which uses its RNA as mRNA. At its 5' end, the RNA genome has a viral protein (VPg) instead of a cap. This is followed by a nontranslated leader sequence, and then a single long protein-coding region (~7000 nucleotides), followed by a poly-A tail. Observations were made that used radioactive amino acid analogues. Short period use of the radioactive amino acids result in labeling of only very long proteins, while longer periods of labeling result in several different short polypeptides. What conclusion is most consistent with the results of the radioactive labeling experiment?

The RNA is only translated into a single long polypeptide, which is then cleaved into shorter ones.

Humans have twenty-three pairs of chromosomes and chimps have twenty-four pairs of chromosomes. What is the most likely explanation for these differences in human and chimp genomes?

The common ancestor of humans and chimps had twenty-four pairs of chromosomes. After the two groups evolved, two human chromosomes fused end to end

HIV is inactivated in the laboratory after a few minutes of sitting at room temperature, but the flu virus is still active after sitting for several hours. What are the practical consequences of these findings?

The flu virus can be transmitted more easily from person to person than HIV

What characteristic of short tandem repeats (STRs) DNA makes it useful for DNA fingerprinting?

The number of repeats varies widely from person to person or animal to animal.

Which of the following statements describes the lysogenic cycle of lambda (λ) phage?

The phage genome replicates along with the host genome.

The herpes viruses are important enveloped DNA viruses that cause disease in vertebrates and in some invertebrates such as oysters. Some of the human forms are herpes simplex virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can later reactivate, replicate again, and infect others. In electron micrographs of HSV infection, it can be seen that the intact virus initially reacts with cell surface proteoglycans, then with specific receptors. This is later followed by viral capsids docking with nuclear pores. Afterward, the capsids go from being full to being "empty." Which of the following best fits these observations?

The viral envelope mediates entry into the cell, the capsid mediates entry into the nuclear membrane, and the genome is all that enters the nucleus.

If a viral host cell has a mutation that interferes with the addition of carbohydrates to proteins in the Golgi, which of the following could likely result?

The viral envelope proteins would not be glycosylated and might not arrive at the host plasma membrane.

A person is most likely to recover from a viral infection if the infected cells _____.

can undergo normal cell division

Viruses use the host's machinery to make copies of themselves. However, some human viruses require a type of replication that humans do not normally have. For example, humans normally do not have the ability to convert RNA into DNA. How can these types of viruses infect humans, when human cells cannot perform a particular role that the virus requires?

The viral genome codes for specialized enzymes not in the host.

Evidence suggests that factors which contribute towards the virulence of E. coli strain O157:H7, a bacterial strain reported to cause several food poisoning deaths, are caused by genes from a virus that infects bacteria. Considering this evidence, which statement most likely explains how the O157:H7 population acquired the genetic variation that distinguishes the strain from harmless E. coli strains, such as those that reside in our intestines?

The virus infected the bacterium, and allowed the bacterial population to replicate with a copy of the phage genome in each new bacterium.

In animals, what is the difference between reproductive cloning and therapeutic cloning?

Therapeutic cloning supplies cells for repair of diseased or injured organs.

Unequal crossing over during prophase I can result in one sister chromosome with a deletion and another with a duplication. A mutated form of hemoglobin, so-called hemoglobin Lepore, exists in the human population. Hemoglobin Lepore has a deleted series of amino acids. If this mutated form was caused by unequal crossing over, what would be an expected consequence?

There should also be persons whose hemoglobin contains two copies of the series of amino acids that is deleted in hemoglobin Lepore.

cut site image In an experiment, DNA from the linear form of the bacteriophage Lambda was cut into fragments using the restriction enzyme Hind III. Restriction enzymes are isolated from bacteria and cut DNA in specific locations. Hind III cuts the Lambda DNA between the adenine nucleotides on the complimentary strands in a specific sequence, as indicated in the diagram, producing eight different size fragments. These fragments are then separated with an electrical current based on size after the DNA fragments are placed in a porous gel, a process called gel electrophoresis. Select an observation that best describes a correct aspect of the two processes of restriction digest and gel electrophoresis:

When separated on a gel, the pattern of DNA bands will be characteristic of those cut with Hind III, different restriction enzymes will not produce these same fragments.

A recent study compared the Homo sapiens genome with that of Neanderthals. The results of the study indicated that there was a mixing of the two genomes at some period in evolutionary history. Additional data consistent with this hypothesis could be the discovery of _____.

a few modern H. sapiens with some Neanderthal sequences

Which of the following problems with animal cloning might result in premature death of the clones?

abnormal gene regulation due to variant methylation

Which of the following viruses would most likely have reverse transcriptase?

an RNA-based lysogenic virus

Yeast cells are frequently used as hosts for cloning because they _____

are eukaryotic cells

Fragments of DNA have been extracted from the remnants of extinct woolly mammoths, amplified, and sequenced. These can now be used to _____.

better understand the evolutionary relationships among members of related taxa

The first class of drugs developed to treat AIDS, such as AZT, were known as reverse transcriptase inhibitors. They worked because they _____.

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

An early step in shotgun sequencing is to _____.

break genomic DNA at random sites

Biologists now routinely test for homology between genes in different species. If genes are determined to be homologous, it means that they are related _____.

by descent from a common ancestor

Transgenic mice are useful to human researchers because they _____.

can be valuable animal models of human disease

Viral infections in plants _____.

can spread within a plant via plasmodesmata

Which of the following accounts for someone who has had regular herpesvirus-mediated cold sore or genital sore flare-ups?

copies of the herpesvirus genome permanently maintained in host nuclei

A researcher lyses a cell that contains nucleic acid molecules and capsomeres of tobacco mosaic virus (TMV). The cell contents are left in a covered test tube overnight. The next day this mixture is sprayed on tobacco plants. We expect that the plants would _____.

develop the typical symptoms of TMV infection

Bioinformatics can be used to scan for short sequences that specify known mRNAs, called _____.

expressed sequence tags

You isolate an infectious substance capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal to analyze the substance and determine the nature of the infectious agent. I. Treat the substance with enzymes that destroy all nucleic acids and then determine whether the substance is still infectious. II. Filterthesubstancetoremoveallelementssmallerthanwhatcanbeeasilyseenunderalight microscope. III. Culture the substance on nutritive medium, away from any plant cells. IV. Treat the sample with proteases that digest all proteins and then determining whether the substance is still infectious. 41) If you already know that the infectious agent was either a viroid or a prion, which method(s) listed above would allow you to distinguish between these two possibilities?

either I or IV

To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would most likely be successful with which of the following methods?

electroporation followed by recombination

Homeotic genes contain a homeobox sequence that is highly conserved among very diverse species. The homeobox is the code for that domain of a protein that binds to DNA in a regulatory developmental process. Therefore, you would expect that _____.

homeotic genes are selectively expressed as an organism develops

After finding a new medicinal plant, a pharmaceutical company decides to determine if the plant has genes similar to those of other known medicinal plants. To do this, the company annotates the genome of the new plant to _____.

identify genes and determine their functions

Which of the following uses labeled probes to visualize the expression of genes in whole tissues and organisms?

in situ hybridization

The herpes viruses are important enveloped DNA viruses that cause disease in vertebrates and in some invertebrates such as oysters. Some of the human forms are herpes simplex virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can later reactivate, replicate again, and infect others. 42) If scientists are trying to use what they know about HSV to devise a means of protecting other people from being infected, which of the following would have the best chance of lowering the number of new cases of infection?

interfere with new viral replication in preexisting cases of HSV

The reason for using Taq polymerase for PCR is that _____.

it is heat stable and can withstand the heating step of PCR

The final step in a Sanger DNA sequencing reaction is to run the DNA fragments on a gel. What purpose does this serve?

it separates DNA fragments generated during the sequencing reaction based on one- nucleotide differences in their size.

Gene therapy requires _____.

knowledge and availability of the normal allele of the defective gene, an ability to introduce the normal allele into the patient, and an ability to express the introduced gene at the correct level, and time, and tissue site within the patient

What are prions?

misfolded versions of normal protein that can cause disease

To make a vaccine against mumps, measles, or rabies, which type of viruses would be useful?

negative-sense ssRNA viruses

In humans, the embryonic and fetal forms of hemoglobin have a higher affinity for oxygen than that of adults. This is due to _____.

nonidentical genes that produce different versions of globins during development.

A virus consisting of a single strand of RNA, which is transcribed into complementary DNA, is a _____.

retrovirus

Because they both produce a reverse transcriptase, long interspersed nuclear elements (LINEs) as transposable elements may be related to _____.

retroviruses

Which of the following is required to make complementary DNA (cDNA) from RNA?

reverse transcriptase

A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using _____.

reverse transcriptase to reconstruct the gene from its mRNA

Which of the following could use reverse transcriptase to transcribe its genome?

ssRNA

A population of viruses with similar characteristics is called a _____.

strain

Proteomics is defined as the _____.

study of the full protein set encoded by a genome

If alternative splicing did NOT occur then _____.

the human genome would likely contain many more genes

It is more difficult to identify eukaryotic genes than prokaryotic genes because in eukaryotes _____.

there are introns

Some viruses can be crystallized and their structures analyzed. One such virus is yellow mottle virus, which infects beans. This virus has a single-stranded RNA genome containing about 6300 nucleotides. Its capsid is 25-30 nm in diameter and contains 180 identical capsomeres. If the yellow mottle virus begins its infection of a cell by using its genome as mRNA, which of the following would you expect to be able to measure?

translation rate

The difference between vertical and horizontal transmission of plant viruses is that vertical transmission is _____.

transmission of a virus from a parent plant to its progeny, and horizontal transmission is one plant spreading the virus to another plant

Retrotransposons _____

use an RNA molecule as an intermediate in transposition

Viruses _____.

use the host cell to copy themselves and make viral proteins