Biology notes Ch. 9, Chapter 10 Mastering Biology, Bio 1310 Chapter 8, Bio 1310 Chapter 12
When one DNA molecule is copied to make two DNA molecules, the new DNA contains
50% of the parent DNA
Approximately what percentage of the human genome is identical to that of a chimpanzee?
98.8%
Genes located close together on the same chromosomes are referred to as ________ genes and generally ________. A. linked; do not sort independently during meiosis B. homologous; are inherited together C. linked; sort independently during meiosis D. codependent; do not sort independently during meiosis
A, linked; do not sort independently during meiosis
Which of the following is only associated with RNA?
uracil
Cloning human genes into the plasmids of bacteria has enabled scientists to __________.
use bacteria as "factories" for protein products
DNA repilcation
uses each strand of a DNA molecule as a template for the creation of a new strand.
Although generally not considered to be alive, a _____ is studied alongside other microbes such as bacteria.
virus
Hershey and Chase's experiment allowed them to discern whether DNA or proteins contain genetic information because __________.
viruses consist only of proteins and DNA and only the DNA was injected into the host cells
Genome sequence analysis suggests that Neanderthals
were lactose intolerant as adults.
Most people afflicted with recessive disorders are born to parents who were A. not affected at all by the disease. B. both affected by the disease. C. slightly affected by the disease, showing some but not all of the symptoms. D. subjected to some environmental toxin that caused the disease in their children.
A, not at all affected by the disease
If the two characteristics that Mendel looked at in his dihybrid cross of smooth yellow peas with wrinkled green peas had been controlled by genes that were located close together on the same chromosome, then the F2 generation _____. A. would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment B. would have contained no individuals that were heterozygous for both genes C. would have contained only individuals that were heterozygous for both genes D. would have contained four phenotypes in a 9:3:3:1 ratio
A, would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment
For most sexually reproducing organisms, Mendel's laws A. explain the biological mechanisms behind why certain genes are dominant or recessive. B. can predict whether offspring will be male or female with 100% accuracy. C. help us understand the global geographic patterns of genetic disease. D. cannot strictly account for the patterns of inheritance of many traits.
C, help us understand the global geographic patterns of genetic disease.
Two identical twins are raised in different environments. They possess _____ genotypes and _____ phenotypes. A. identical ... dissimilar B. contrasting ... identical C. identical ... variable D. identical ... identical
C, identical ... variable
Linked genes are inherited together. This is because linked genes _____. A. govern traits (such as hair texture and hair color) that are functionally related B. govern traits that have nothing to do with one another C. are on the same chromosome D. have the same alleles residing on them
C, are on the same chromosome
Sickle-cell disease is an example of A. multiple alleles and pleiotropy. B. multiple alleles, pleiotropy, and blended inheritance. C. co-dominance and pleiotropy. D. co-dominance and multiple alleles.
C, co-dominance and pleiotropy.
The mechanism that "breaks" the linkage between linked genes is A. independent assortment. B. pleiotropy. C. crossing over. D. co-dominance.
C, crossing over.
Linked genes generally A. reflect a pattern of codominance. B. show incomplete dominance. C. do not follow the laws of independent assortment. D. show pleiotropy.
C, do not follow the laws of independent assortment.
Sturtevant's genetic mapping _____. A. orders genes on a chromosome based on their location with respect to a stained band B. can be constructed only for sex chromosomes C. orders genes on a chromosome based on recombination frequencies D. shows the ordering and exact spacing of genes on a chromosome
C, orders genes on a chromosome based on recombination frequencies
A single allele that controls more than one character is said to be _____. A. autotrophic B. polygenic C. pleiotropic D. linked
C, pleiotropic
The inheritance of height and weight can best be described as __________. A. Mendelian (dominant-recessive) inheritance B. the results of a bad lifestyle C. polygenic and multifactorial D. being caused by microorganisms
C, polygenic and multifactorial
Most genetic disorders of humans are caused by A. a mutation that occurs in the egg, sperm, or zygote. B. dominant alleles. C. recessive alleles. D. multiple alleles.
C, recessive alleles
What must happen before a cell can begin mitosis?
The chromosomes must be duplicated.
Which of the following statements characterizes the lytic cycle of a viral infection?
The cycle typically leads to the lysis of the host cell.
Consider the following sentence: "The dog did not eat." Which of the following variations of this sentence is most like a frameshift mutation?
The dod idn ote at.
Consider the following sentence: "The dog did not eat." Which of the following variations of this sentence is most like a base substitution mutation?
The doe did not eat.
Which of the following techniques were most helpful to Watson and Crick in determining the structure of DNA?
X-ray crystallography
The way that genetic material of a bacteriophage enters a bacterium is most like the way that
a drug is injected with a hypodermic needle.
Any change in the nucleotide sequence of DNA is called
a mutation.
Which of the following describes a complete nucleotide?
a nitrogenous base, a sugar, and a phosphate group
An enzyme that "cuts" DNA at a specific sequence of nucleotide bases is called __________.
a restriction enzyme
With the exception of identical twins, siblings who have the same two biological parents are likely to look similar, but not identical, to each other because they have
a similar but not identical combination of traits
The shape of a DNA molecule is most like
a twisted rope ladder.
Which pieces of evidence would be considered the best for establishing biological relatedness?
a very close match in the DNA profile
A protein coat enclosing a viral genome is known as a(n)
capsid
The protein coat that surrounds the nucleic acid of a virus is called a ______.
caspid
Which of the following occurs during interphase?
cell growth and duplication of the chromosomes
A benign and a malignant tumor differ in that
cells of a benign tumor remain within the tumor, whereas cells of a malignant tumor can spread to other body tissues
what is in the center of two sister chromatids
centromere
Which of the following options most accurately lists the sequence of events in translation?
codon recognition → peptide bond formation → translocation → termination
Which of the following statements best defines recombinant DNA technology?
combining genes from different sources
restriction enzymes
cut DNA at specific sites.
The process by which the cytoplasm of a eukaryotic cell divides to produce two cells is called
cytokinesis
In anaphase I
homologous chromosomes move toward opposite poles
A ________ is a viral genome that has inserted itself into the genome of its host.
prophage
Viral DNA incorporated into host cell DNA is known as a(n)
prophage
Crossing over occurs during
prophase I
Synapsis occurs during
prophase I
DNA polymerase is a heat-sensitive enzyme. What is one thing that would need to be considered concerning the activity of this enzyme in PCR when the temperature is heated during each cycle to separate the DNA strands?
that the DNA polymerase could be denatured
What genetic information does cDNA contain?
the DNA sequence of expressed genes
A large and increasing number of genetic tests are available to prospective parents and children. Even as these testing methods become more and more sophisticated, what is one thing technology will never solve?
the ability to prescribe the correct course of action based on test results
What is different concerning the DNA in bacterial cells as opposed to eukaryotic cells?
the amount of DNA present whether the DNA is housed in a nucleus or not whether the DNA is linear or circular all of the above are differences between prokaryotic and eukaryotic DNA
At the start of mitotic anaphase,
the centromeres of each chromosome come apart.
Which of the following takes place during translation?
the conversion of genetic information from the language of nucleic acids to the language of proteins
The "one gene-one polypeptide" theory states that
the function of an individual gene is to dictate the production of a specific polypeptide.
Many genetic disorders can be detected before birth. Procedures include _____, which is noninvasive, or _____, which allows the chromosomes of the fetus to be examined. Alternatively, maternal blood samples can be taken and tested for _____.
ultrasound imaging, chorionic villus sampling , and AFP
Looking into your microscope, you spot an unusual cell. Instead of the typical rounded cell shape, the cell has a very narrow middle separating two bulging ends. It sort of looks like the number 8! You realize that this cell is
undergoing cytokinesis
The envelope of a mumps virus
helps the virus enter the cell.
What makes up a pair of homologous chromosomes
two sister chromatids
Eukaryotic chromosomes differ from prokaryotic chromosomes in that they
are housed in a membrane-enclosed nucleus.
biotechnology
has been around since the dawn of civilization.
Select the three true statements about crossing over.
1. During meiosis II, sister chromatids separate into four different gametes. 2. During prophase I of meiosis I, homologous paternal and maternal chromosomes line up at the metaphase plate. 3. A hybrid chromosome that has crossed over will contain pieces of both the maternal and paternal chromosomes.
Name the events of meiosis in order
1. homologous chromosomes pair up 2. non sister chromatids form chiasmata 3. crossing over occurs 4. homologous chromosomes separate 5. sister chromosomes separate 6. four haploid gametes are produced
Approximately what percentage of the human genome actually encodes proteins or functional RNA molecules?
1.5%
Which of the following events occurs during transcription?
A molecule of RNA is formed based on the sequence of nucleotides in DNA.
________ marks the end of a gene and causes transcription to stop.
A terminator
If independent assortment did not occur, which of the following would be true? A. Genes for two different traits would be inherited together as a pair. B. Each sperm and egg would carry more than one allele for a specific gene. C. A dihybrid cross of heterozygous individuals would yield four different phenotypes. D. Meiosis II would not be required to produce gametes, as meiosis I would be sufficient.
A, Genes for two different traits would be inherited together as a pair.
The chromosome theory of inheritance is based upon which of the following sets of observations? A. Genes segregate; chromosomes come in pairs. B. Genes occur as singular entities; chromosomes come in pairs. C. Genes assort together; chromosomes come in pairs. D. Genes remain associated with one another; so do chromosomes.
A, Genes segregate; chromosomes come in pairs.
Which of the following statements best explains why dominant alleles that cause lethal disorders are less common than recessive alleles that cause lethal disorders? A. Most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce. B. The presence of a lethal dominant allele causes sterility. C. Lethal disorders caused by dominant alleles are usually more severe than lethal disorders caused by recessive alleles. D. Unlike lethal disorders caused by recessive alleles, lethal disorders caused by dominant alleles usually cause the death of the embryo.
A, Most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce.
Imagine you're counseling a couple who have undergone carrier screening for Tay-Sachs disease. The man is a carrier, and the woman does not carry the Tay-Sachs allele. How should you advise them? A. They should be informed that if they have a child, the child will not have Tay-Sachs disease but will have a 50% chance of being a carrier of the Tay-Sachs allele. B. They should be informed that if they have a child, there is a 50% chance that the child will have Tay-Sachs disease. C. They should be informed that if they conceive a child, the child will have Tay-Sachs disease. D. They should be informed that if they have a child, there is a 25% chance that the child will have Tay-Sachs disease.
A, They should be informed that if they have a child, the child will not have Tay-Sachs disease but will have a 50% chance of being a carrier of the Tay-Sachs allele.
A person with AB blood illustrates the principle of A. co-dominance. B. incomplete dominance. C. pleiotropy. D. polygenic inheritance.
A, co-dominance
The expression of both alleles for a trait in a heterozygous individual illustrates A. co-dominance. B. polygenic inheritance. C. pleiotropy. D. incomplete domin
A, co-dominance.
The individual features of all organisms are the result of A. genetics and the environment. B. genetics. C. the environment and individual needs. D. the environment.
A, genetics and the environment.
Which of the following is an example of incomplete dominance in humans? A. hypercholesterolemia B. albinism C. ABO blood groups D. skin color
A, hypercholesterolemia
Human genetic disorders _____. A. are most often dominant B. are almost never observed in modern societies C. are most often recessive D. are almost always life-threatening
C, are most often recessive
Imagine that a deaf male has a child with a hearing female. You know that the male must have the genotype dd, but the female could be either Dd or DD. If the couple's first child has hearing, can you determine the mother's genotype?
Her genotype cannot be determined.
If one parent is blood type AB and the other is type O, what fraction of their offspring are expected to have blood type A? A. O B. 0.5 C. 0.75 D. 1.0
B, 0.5
You conduct a dihybrid cross. A ________ ratio would make you suspect that the genes are linked. A. 3:1 B. 12:1:1:4 C. 9:3:3:1 D. 1:1:1:1
B, 12:1:1:4
Snapdragons show incomplete dominance in their flowers. A pink snapdragon is crossed with a red snapdragon. What color(s) are the offspring? A. 50% red, 50% white B. 50% red, 50% pink C. 100% red D. 100% pink
B, 50% red, 50% pink
Blood samples are taken from the heel of newborn babies to test for a mutation in the PKU gene, which, if left untreated and in severe cases, can lead to mental retardation, reduced skin pigmentation, and seizures. Which concept is being illustrated by this example? A. polygenic inheritance B. pleiotropy C. incomplete dominance D. co-dominance
B, pleiotropy
Two parents of mixed ethnicity have twins, one of which is born white and one of which is born black. This is because of _____. A. exposure to sunlight B. the polygenic nature of skin color genes C. the pleiotropic effects of skin color genes D. the inheritance of two linked skin color genes
B, the polygenic nature of skin color genes
Justin's parents both have type AB blood, and Brittany's parents also both have type AB blood. What are the chances that Justin and Brittany's son Theodore has type A blood? A. 75% B. 25% C. 0% D. 100%
C, 0%
Which of the following statements is false? A. Incomplete dominance supports the blending hypothesis. B. The impact of a single gene on more than one character is called pleiotropy. C. ABO blood groups can provide evidence of paternity. D. The four blood types result from various combinations of the three different ABO alleles.
C, ABO blood groups can provide evidence of paternity.
Two individuals decide to have children. The expected blood group genotypes are 50% of blood type A, and 25% each of blood types AB and B. What genotypes are the parents? A. IA i x ii B. IB i x IA IB C. IA i x IA IB D. IA i x IB i
C, IA i x IA IB
The chromosome theory of inheritance states that A. chromosomes that exhibit mutations are the source of genetic variation. B. the behavior of chromosomes during mitosis accounts for inheritance patterns. C. the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance. D. humans have 46 chromosomes.
C, the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance.
n people with sickle-cell disease, red blood cells break down, clump, and clog blood vessels. Blood vessels and broken cells accumulate in the spleen. Among other symptoms, this leads to physical weakness, heart failure, pain, and brain damage. Such a suite of symptoms can be explained by __________. A. the polygenic nature of sickle-cell disease B. a bacterial infection interacting with the sickle-cell allele C. the pleiotropic effects of the sickle-cell allele D. side effects of the drugs used to treat sickle-cell disease
C, the pleiotropic effects of the sickle-cell allele
What is the transcription product of the sequence GCTAGCGATGAC?
CGAUCGCUACUG
Which of the following statements regarding cell division is false?
Cell division is common in eukaryotes but rare in prokaryotes.
You are interested in designing an experiment to test the hypothesis that frogs use the same genetic code as humans. Which of the following experiments would not give you useful data to test this hypothesis?
Compare nucleotide sequences of promoters from similar frog and human genes.
Which of the following statements regarding the differences between mitosis and meiosis is false?
Crossing over is a phenomenon that creates genetic diversity during mitosis.
At the end of the mitotic (M) phase, the cytoplasm divides in a process called
Cytokinesis
Which of the following terms refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes? A. co-dominance B. pleiotropy C. incomplete dominance D. polygenic inheritance
D, polygenic inheritance
Crossing over ________ genes into assortments of ________ not found in the parents. A. combines linked; genes B. recombines unlinked; genes C. combines unlinked; alleles D. recombines linked; alleles
D, recombines linked; alleles
The term binary fission is best applied to
prokaryotes
High levels of LDL cholesterol in the bloodstream can be the result of familial hypercholesterolemia, an inherited condition that displays incomplete dominance. In a family with a severely affected father and an unaffected mother, what percentage of their children are expected to have higher than normal blood cholesterol? A. 0% B. 25% C. 50% D. 100%
D, 100%
Flower color in snapdragons is an example of incomplete dominance. If a red-flowered plant is crossed with a white-flowered plant, the F1 generation has pink flowers. If a pink-flowered plant is crossed with another pink-flowered plant, the expected progeny plants will be __________. A. 100% pink B. 100% red C. 50% pink and 50% red D. 25% red, 50% pink, and 25% white
D, 25% red, 50% pink, and 25% white
In breeding pure-breeding large and small strains of mice, you cross individuals of each strain and note that their offspring are intermediate in size. Two models (explanations) to account for this result are (1) that body size in these strains is due to one gene with alleles that show incomplete dominance and (2) that body size is a polygenic trait. How could you distinguish between these models? A. Intercross the F1 and see if there is a range of sizes in the F2 (consistent with the incomplete dominance model) or if the F2 contains two size classes (consistent with the polygenic model). B. Intercross the F1 and see if there is a range of sizes in the F2 (consistent with the incomplete dominance model) or if the F2 contains only three size classes (consistent with the polygenic model). C. Body size is known to be an incompletely dominant trait. D. Intercross the F1 and see if the F2 contains three size classes (consistent with the incomplete dominance model) or if there is a range of sizes (consistent with the polygenic model).
D, Intercross the F1 and see if the F2 contains three size classes (consistent with the incomplete dominance model) or if there is a range of sizes (consistent with the polygenic model).
Which of the following statements regarding sickle-cell disease is false? A. Persons who are heterozygous for sickle-cell disease are also resistant to malaria. B. About one in 10 African Americans is a carrier of sickle-cell disease. C. All of the symptoms of sickle-cell disease result from the actions of just one allele. D. Sickle-cell disease causes white blood cells to be sickle-shaped.
D, Sickle-cell disease causes white blood cells to be sickle-shaped.
In a particular species of mammal, black hair (B) is dominant to green hair (b), and red eyes (R) are dominant to white eyes (r). When a BbRr individual is mated with a bbrr individual, offspring are produced in a ratio of 5 black hair and red eyes : 5 green hair and white eyes : 1 black hair and white eyes : 1 green hair and red eyes. Which of these explanations accounts for this ratio? A. The genes for hair color and the genes for eye color are carried on different chromosomes. B. The expected results did not take genetic recombination into account. C. Green-haired individuals have a higher prenatal mortality than black-haired individuals. D. The genes for hair color and eye color are linked.
D, The genes for hair color and eye color are linked.
Tay-Sachs disease runs in Rebecca's family. On a family pedigree, she saw a shaded circle. This represented: A. a female carrier B. a male with Tay-Sachs C. a male carrier D. a female with Tay-Sachs
D, a female with Tay-Sachs
Previously, it was thought that the blending hypothesis explained inheritance. The blending hypothesis maintained that __________. A. the characters governed by genes in the egg are different from the characters governed by genes in the sperm B. many genes are lost in their transmission to offspring, but the remaining genes gradually reproduce the lost genes C. mutation is the major source of new gene combinations D. after a mating, genes of the two parents are mixed in the offspring and lose their individual identities
D, after a mating, genes of the two parents are mixed in the offspring and lose their individual identities
The crossover percentage between two different genes is _____. A. dependent on the sex of the parent B. greater as the distance between the two genes decreases C. dependent on whether dominant or recessive alleles are carried by the two genes D. greater as the distance between the two genes increases
D, greater as the distance between the two genes increases
A carrier of a genetic disorder who does not show symptoms is most likely to be ________ to transmit it to offspring. A. heterozygous for the trait and unable B. homozygous for the trait and able C. homozygous for the trait and unable D. heterozygous for the trait and able
D, heterozygous for the trait and able
All the offspring of a cross between a red-flowered plant and a white-flowered plant have pink flowers. This means that the allele for red flowers is ________ to the allele for white flowers. A. dominant B. recessive C. co-dominant D. incompletely dominant
D, incompletely dominant
Our understanding of the role played by genes in many human characteristics is advancing rapidly in, for example, body size, performance on IQ tests, and personality traits. In this new genetic era, the role of the environment __________. A. is always far more important than genes in the development of complex human traits B. can largely be discounted in the development of complex human traits C. is important only in influencing personality traits D. is to work with genes in complex and often unknown ways in the development of these traits
D, is to work with genes in complex and often unknown ways in the development of these traits
Which of the following kinds of data could be used to map the relative position of three genes on a chromosome? A. the frequencies of mutations in the genes B. the frequencies with which the genes exhibit incomplete dominance over each other C. the frequencies with which the genes are inherited from the mother and from the father D. the frequencies with which the corresponding traits occur together in offspring
D, the frequencies with which the corresponding traits occur together in offspring
Which one of the following does not play a role in translation?
DNA
"Sticky ends" are
DNA fragments with single-stranded ends.
The molecule that seals the gaps between the pieces of DNA in the lagging strand is
DNA ligase
What enzyme joins DNA fragments?
DNA ligase
Which statement about DNA replication is FALSE?
DNA ligase adds nucleotides to the lagging strand.
Two new strands of DNA molecules grow as bases are added by the enzyme _____.
DNA polymerase
Which of the following enzymes catalyzes the elongation of a new DNA strand?
DNA polymerase
Which of the following occurs during DNA replication?
DNA polymerase elongates the daughter strand, adding new nucleotides to the 3′ end of the molecule. The molecule grows 5′ to 3′ but is therefore read 3′ to 5′.
Which of the following build(s) new strands of DNA?
DNA polymerases
The first step of bacterial replication is
DNA replication
Which of the following statements about DNA technology is false?
DNA technology is now used to create cells that can identify and kill cancer cells.
Considering only the steps that take place during translation, which of the following is not needed in order for translation to occur?
DNA template
Which of the following statements regarding DNA is false?
DNA uses the nitrogenous base uracil.
Which of the following options best depicts the flow of information when a gene directs the synthesis of a cellular component?
DNA → RNA → protein
Frederick Griffith was one of the leading scientists looking at the genetic role of DNA. He was working on two strains of Streptococcus pneumoniae: The rough strain (R) did not cause pneumonia, but the smooth strain (S) did. When Griffith heat-killed the S strain and gave both the heat-killed S strain and the R strain to mice, the mice developed pneumonia and died. What happened in this experiment that caused the mice to develop pneumonia?
Even though the S strain had been heat-killed, it changed the R strain.
Gel electrophoresis separates DNA molecules on the basis of size. Which of the following DNA molecules would move the slowest?
F plasmid (100 kb)
What are the steps of the cell cycle for eukaryotic cells
G1 phase --> S phase --> G2 phase --> Mitosis --> cytokinesis -->
Which phases of the eukaryotic cell cycle occur during Interphase
G1, S phase, and G2
If one strand of DNA is CGGTAC, then the corresponding strand would be
GCCATG.
Which of the following statements about herpesviruses is false?
Herpesviruses reproduce inside the host cell's mitochondria.
Which of the following people conducted the experiments that demonstrated that DNA is the genetic material of bacteriophages?
Hershey and Chase
Below are three statements. Which of the following choices properly matches the statements with the correct biological processes? I. This occurs in the nucleus of eukaryotic cells. II. Transfer RNAs bind amino acids in the cytoplasm. III. A polymerase enzyme is required.
I: replication; II: translation; III: transcription
Eukaryotic cells spend most of their cell cycle in which phase?
Interphase
What is the function of the polymerase chain reaction (PCR)?
It can make a large amount of DNA from a tiny amount.
John and Jane are planning a family, but since each has a brother who has sickle-cell disease, they are concerned that their children may develop sickle-cell disease. Neither John, Jane, nor their respective parents have the disease. They consult a genetic counselor who tells them that___?
It's possible that none of their children will have the disease, but blood tests on them both will be required to make sure.
The chromosomes line up in the center of the cell during which phase of mitosis?
Metaphase
Which of the following statements regarding mitosis and meiosis is false?
Mitosis produces daughter cells with half the number of chromosomes as the parent cell.
What are the main differences between mitosis and meiosis?
Mitosis: genetically identical daughter cells through a single cell division Meiosis: genetically different daughter cells through multiple cell divisions
Which statement about genome sequencing is false?
Most of the genomes that have been sequenced to date are eukaryotes.
Prokaryotic organisms have a single origin of replication, whereas eukaryotic organisms have many origins where replication occurs simultaneously. Which of the following is the most probable reason for this observation?
Prokaryotic DNA is much smaller than eukaryotic DNA.
The centrosomes move away from each other and the nuclear envelope breaks up during which phase of mitosis?
Prophase
The phase of mitosis during which the mitotic spindle begins to form is
Prophase
Reverse transcription, carried out by retroviruses, is the process by which _____.
RNA information is copied into DNA
Which of the following enzymes catalyzes the production of a strand of RNA from DNA?
RNA polymerase
Which of the following statements regarding RNA is false?
RNA uses the sugar dextrose
In a PCR reaction, the strands of DNA are first separated by
heating
Which step in this process requires use of restriction enzymes?
Step B
During DNA replication, which nucleotide will bind to an A nucleotide in the parental DNA?
T
The chromosomes arrive at the poles and nuclear envelopes form during which phase of mitosis?
Telophase
How would the shape of a DNA molecule change if adenine paired with guanine and cytosine paired with thymine?
The DNA molecule would have irregular widths along its length.
Which of the following statements regarding a DNA double helix is true?
The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine.
Which of the following statements regarding the cell cycle control system is false?
The cell cycle control system operates independently of the growth factors.
Which statement about DNA replication is CORRECT?
The leading strand is built continuously, and the lagging strand is built in pieces.
Which of the following statements is false?
The lysogenic cycle typically results in the rapid lysis of all infected cells.
A single base mutation occurs in a gene that codes for a protein due to an error in DNA replication. Which of the following outcomes would possibly not occur?
The mutation may result in mRNA being made from the protein.
Normal genes have a promoter followed by a start codon. In a mutant gene, the "A" in the start codon has been deleted. Which of the following is not a possible outcome?
The normal protein will be produced.
Which of the following statements about ribosomes is false?
The ribosomes of prokaryotes and eukaryotes are the exactly the same in structure and function.
Which of the following statements regarding the structure of DNA is false?
The sequence of nucleotides along the length of a single DNA strand is restricted by the base-pairing rules.
Which of the following statements is false?
The start codon can be different depending on what kind of protein is to be translated.
Which of the following statements is true about double-stranded DNA?
The strands run in opposite directions.
Which of the following statements about plant viruses is false?
There are many successful ways to rid infected plants of a virus.
How do retroviruses such as HIV differ from other viruses?
They contain the enzyme reverse transcriptase.
Which of the following statements regarding the flow of genetic information is false?
Transcription occurs in the cytoplasm of eukaryotic cells.
Which of the following statements regarding viral diseases is false?
Very few new human diseases have originated in other animals because the genetic differences are too great.
When is PCR particularly applicable?
When there are small quantities of DNA to analyze
It is possible to synthesize proteins in vitro (in a test tube) without the use of living cells. If starting from a mature mRNA transcript, which of the following components would not be needed to do this?
adenine molecules
The four bases contained in DNA are _____.
adenine, guanine, cytosine, thymine
Crossing over is important because it
allows the exchange of different versions of genes between homologous chromosomes
The sister chromatids separate and begin moving toward opposite poles of the cell during which phase of mitosis?
anaphase
Insulin used for the treatment of diabetes in humans is now obtained from _____.
bacteria
A _____________ is a virus that specifically infects bacteria.
bacteriophage
Why does a DNA strand grow only in the 5' to 3' direction?
because DNA polymerases can only add nucleotides to the 3' end of the growing molecule
Golden Rice is golden in color because it is rich in
beta-carotene
Bacteria divide by:
binary fission
During the replication of DNA molecules, __________.
both strands of the parent molecule act as templates
During DNA replication, _____.
each parental strand serves as a template for the synthesis of a complementary strand
The 2009 H1N1 flu virus
evolved through the genetic reshuffling of viruses that infect humans, birds, and pigs.
Plants are being engineered to produce their own insecticides; therefore, __________.
farmers can reduce chemical use
Which of the following is a feature of plant cell division that distinguishes it from animal cell division?
formation of a cell plate
We would expect that a 15-nucleotide sequence that includes a stop codon at the end (as part of the 15-nucleotide sequence) will direct the production of a polypeptide that consists of
four amino acids.
The function of meiosis is to make
four cells with a haploid number of chromosomes
Which of the following terms associated with transcription describe regions of nucleic acid?
gene, prometer, terminator
Human growth hormone is a secreted protein that stimulates growth and cell reproduction. In the 1960s it was discovered that this was an effective treatment for a form of dwarfism. However, before it was genetically engineered, it was _____.
harvested from cadavers
The advantage of being able to clone the gene for human insulin is that
human insulin is less likely to cause harmful side effects than cow, pig, or horse insulin.
The two strands of a DNA molecule are joined to each other through _____.
hydrogen bonds between nucleotide bases
Where does meiosis occur in animals?
in the ovaries/testes
Which of the following occurs when RNA polymerase attaches to the promoter DNA?
initiation of a new RNA molecule
Both mitosis and meiosis are preceded by
interphase
To date, the "easy" part of gene therapy has been _____.
isolating and cloning the normal gene
Sister chromatids are
joined together at a centromere.
Which of the following is a function of a tRNA molecule?
joining to only one specific type of amino acid
The _______________ is a viral life cycle in which the virus inserts its genome into the genome of its host, where it may remain dormant for long periods.
lysogenic cycle
The ___________ is a viral life cycle that results in bursting of the host cell.
lytic cycle
Which of the following does not occur during RNA processing?
mRNA attaches to the small subunit of a ribosome.
Which of the following is a correct statement about mRNA?
mRNA moves from the nucleus to the cytoplasm following RNA processing.
In the genetic code,
many amino acids are specified by more than one codon.
After fertilization, the resulting zygote begins to divide by
mitosis
Which phases of the eukaryotic cell cycle occur during Mitotic (M) phase?
mitosis and cytokinesis
A physical or chemical agent that changes the nucleotide sequence of DNA is called a(n)
mutagen.
Monomers for the synthesis of DNA are called __________.
nucleotides
The monomers of DNA and RNA are
nucleotides
A uracil nucleotide is a __________ nitrogenous base attached to the __________, with the 5′ carbon of the sugar attached to a phosphate group.
one-ringed : carbon of a sugar that has an OH group at the 2′ carbon
When a T2 bacteriophage infects an Escherichia coli cell, which part of the phage enters the bacterial cytoplasm?
only the DNA
One type of virus that infects bacteria is called a
phage
Independent orientation of chromosomes at metaphase I results in an increase in the number of
possible combinations of characteristics.
Restriction enzymes specifically recognize and cut short sequences of DNA called
restriction sites
The site of translation is
ribosomes in the cell cytoplasm.
What is the correct sequence of events that occur in a PCR reaction?
separation of DNA strands; addition of primers; use of DNA polymerase to produce second strand of DNA
Multiple origins of replication on the DNA molecules of eukaryotic cells serve to
shorten the time necessary for DNA replication.
Prior to mitosis and after S phase, each chromosome of a eukaryotic cell consists of a pair of identical structures called
sister chromatids
Which of the following is a key difference between meiosis and mitosis?
synapsis occurs (in meiosis)
A eukaryotic cell has a nuclear envelope that allows tRNA molecules, but not mRNA molecules, to leave the nucleus. Which of the following processes will not be able to take place in this cell?
tRNAs binding to codons
The copying mechanism of DNA is most like
taking a picture of yourself and of your reflection in a mirror.
In an important experiment, radioactively labeled bacteriophages were allowed to infect bacteria. In the first trial, the phages contained radioactive DNA, and radioactivity was detected in the bacteria. Next, other phages containing radioactive protein were allowed to infect bacteria, and radioactivity was not detected in the bacteria. These experiments led to the conclusion that _____.
the genes of this phage were made of DNA
In order for gene therapy to be permanent in the patient being treated,
the normal gene must be transferred to somatic cells that can continuously multiply.
The directions for each amino acid in a polypeptide are indicated by a codon that consists of ________ nucleotides in an RNA molecule.
three
Experiments have demonstrated that the "words" of the genetic code (the units that specify amino acids) are
three-nucleotide sequences.
The transfer of genetic information from DNA to RNA is called
transcription