biology 1113 questions (chapters 14-19)
What is the probability that the 1st and the 2nd offspring will have purple flowers?
9/16
Which of the following enzymes creates a primer for DNA polymerase? A. Primase B. Ligase C. Helicase D. Topoisomerase
A. Primase
In eukaryotes, general transcription factors
bind to other proteins or to a sequence element within the promoter called the TATA box.
Alternative RNA splicing:
can allow the production of proteins of different sizes and functions from a single mRNA.
A mutation that inactivates the regulatory gene of a repressible operon in an E. coli cell would result in
continuous transcription of the structural genes controlled by that regulator
After DNA replication is completed, _____.
each new DNA double helix consists of one old DNA strand and one new DNA strand
The first step in the replication of DNA is catalyzed by _____.
helicase
Imagine a genetic counselor working with a couple who have just had a child who is suffering from Tay-Sachs disease. Neither parent has Tay-Sachs, nor does anyone in their families. Which of the following statements should this counselor make to this couple?
"Because you have had one child with Tay-Sachs, you must each carry the allele. Any child you have has a 25% chance of having the disease."
1. In a monohybrid cross, what is the probability that the first offspring will have purple flowers? 2. What is the probability that the 2nd offspring will have purple flowers? (Same cross)
1. 3/4 2. 3/4
In the same mouse species, a third unlinked gene (gene C/c) also has an epistatic effect on fur color. The presence of the dominant allele C (for color), allows the A/a and B/b genes to be expressed normally. The presence of two recessive alleles (cc), on the other hand, prevents any pigment from being formed, resulting in an albino (white) mouse. Match the phenotypes on the labels at left to the genotypes listed below. Labels can be used once, more than once, or not at all. 1. AaBbcc 2. AAbbCc 3. AaBBCC 4. Aabbcc 5. aaBbCc 6. AABBcc
1. albino 2. agouti brown 3. agouti black 4. solid color, black 5. albino 6. albino
The inheritance of eye color in Drosophila is controlled by genes on each of the fly's four chromosome pairs. One eye-color gene is on the fly's X chromosome, so the trait is inherited in a sex-linked manner. For this sex-linked trait, the wild-type (brick red) allele is dominant over the mutant vermilion (bright red) allele. A homozygous wild-type female fly is mated with a vermilion male fly. X+X+ x XvY Predict the eye colors of F1 and F2 generations. (Assume that the F1 flies are allowed to interbreed to produce the F2 generation.)Drag the correct label to the appropriate location in the table. Labels can be used once, more than once, or not at all. 1. F1 females 2. F1 males 3.F2 females 4. F2 males
1. all wild type 2. all wild type 3. all wild type 4. 1/2 wild type, 1/2 vermilion
If the sequence ATGCATGTCAATTGA were mutated such that a base were inserted after the first G and the third T were deleted, how many amino acids would be changed in the mutant protein?
2
In addition to A and a, the "agouti" gene has a third allele, AY . Here is some information about the inheritance of the AY allele. The AY allele is dominant to both A and a. The homozygous genotype (AYAY ) results in lethality before birth. The heterozygous genotypes (AYA or AYa) result in yellow fur color, regardless of which alleles are present for the B/b gene. (This effect exhibited by the AY allele is known as epistasis--when the expression of one gene masks the expression of a second gene.) Suppose you mate two mice with the genotypes AYaBb x AYaBb . Considering only the live-born offspring, what would be the expected frequency of mice with yellow fur? (For help getting started, see Hint 1.) Express your answer as a fraction using the slash symbol and no spaces (for example, 1/16).
2/3
Imagine a locus with four different alleles for fur color in an animal. The alleles are named Da, Db, Dc, and Dd. If you crossed two heterozygotes, DaDb and DcDd, what genotype proportions would you expect in the offspring?
25% DaDc, 25% DaDd, 25% DbDc, 25% DbDd
In mice, agouti fur is a dominant trait resulting in individual hairs having a light band of pigment on an otherwise dark hair shaft. A mouse with agouti fur is shown here, along with a mouse with solid color fur, which is the recessive phenotype (A = agouti; a = solid color). A separate gene, which is not linked to the agouti gene, can result in either a dominant black pigment or a recessive brown pigment (B = black; b = brown). A litter of mice from the mating of two agouti black parents includes offspring with the following fur colors:solid color, black solid color, brown (sometimes called chocolate)agouti black agouti brown (sometimes called cinnamon) What would be the expected frequency of agouti brown offspring in the litter?
3/16
In the same mouse species, a fourth unlinked gene (gene P/p) also affects fur color. For mice that are either homozygous dominant (PP) or heterozygous (Pp), the organism's fur color is dictated by the other three genes (A/a, B/b, and C/c). For mice that are homozygous recessive (pp), large patches of the organism's fur are white. This condition is called piebaldism. In a cross between two mice that are heterozygous for agouti, black, color, and piebaldism, what is the probability that offspring will have solid black fur along with large patches of white fur? (Hint: Consider each gene separately; then use the multiplication rule. For more help getting started, see Hint 1.) Express your answer as a fraction using the slash symbol and no spaces (for example, 3/16).
9/256
If you want to design a test cross to determine the genotype of one of the black baby rabbits what should you cross it with?
A white rabbit
Suppose a mother with type B blood and a father with type A blood have a child who is type O. What are the other possible blood types of subsequent offspring?
A, B, AB and O
Which of the following cell types is likely to demonstrate the lowest level of telomerase activity? A. Somatic cells B. germ cells C. cancer cells D. Somatic cells, germ cells, and cancer cells are likely to demonstrate identical levels of telomerase activity
A. Somatic cells
Which of the following is most likely to have a small protein called ubiquitin attached to it? A. a cyclin that usually acts in G1, now that the cell is in G2 B. an mRNA produced by an egg cell that will be retained until after fertilization C. a regulatory protein that requires sugar residues to be attached D. an mRNA that is leaving the nucleus to be translated E. a cell surface protein that requires transport from the ER
A. a cyclin that usually acts in G1, now that the cell is in G2
Eukaryotic telomeres replicate differently than the rest of the chromosome. This is a consequence of which of the following? A. gaps left at the 5' end of the lagging strand B. the "no ends" of a circular chromosome C. DNA polymerase that cannot replicate the leading strand template to its 5' end D. the evolution of telomerase enzyme E. gaps left at the 3' end of the lagging strand because of the need for a primer
A. gaps left at the 5' end of the lagging strand
A researcher found a method she could use to manipulate and quantify phosphorylation and methylation in embryonic cells in culture. One of her colleagues suggested she try increased methylation of C nucleotides in a mammalian system. Which of the following results would she most likely see? A. inactivation of the selected genes B. decreased binding of transcription factors C. decreased chromatin condensation D. activation of histone tails for enzymatic function
A. inactivation of the selected genes
Which of the following sequences would result from replication of this DNA template strand? 3′-AAGTCAGT-5′ A. 5′-AAGTCAGT-3′ B. 5′-TTCAGTCA-3′ C. 3′-TTCAGTCA-5′ D. 3′-AAGTCAGT-5′
B. 5′-TTCAGTCA-3′
Which of the following statements about mutations is false? A. Addition and deletion mutations disrupt the primary structure of proteins. B. A knock-out mutation results in a total absence of the mutated protein. C. A deletion mutation results in the loss of a base in the DNA sequence. D. An addition mutation results in an added base in the DNA sequence.
B. A knock-out mutation results in a total absence of the mutated protein.
Which of the following contradicts the one-gene, one-enzyme hypothesis? A. Sickle cell anemia results in defective hemoglobin. B. A single antibody gene can code for different related proteins, depending on the splicing that takes place posttranscriptionally. C. Alkaptonuria results when individuals lack a single enzyme involved in the catalysis of homogentisic acid D. A mutation in a single gene can result in a defective protein.
B. A single antibody gene can code for different related proteins, depending on the splicing that takes place posttranscriptionally.
Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the promoter for the lac operon to the region between the beta galactosidase (lacZ) gene and the permease (lacY) gene, which of the following would be likely? A. The three structural genes will be expressed normally. B. Beta galactosidase will not be produced. C. The cell will continue to metabolize but more slowly. D. RNA polymerase will no longer transcribe permease E. The operon will no longer be inducible
B. Beta galactosidase will not be produced.
Researchers found E. coli that had mutation rates 100 times higher than normal. Which of the following is the most likely cause of these results? A. The single-stranded binding proteins were malfunctioning. B. The proofreading mechanism of DNA polymerase was not working properly C. There were one or more mismatches in the RNA primer. D. The DNA polymerase was unable to add bases to the 3' end of the growing nucleic acid chain.
B. The proofreading mechanism of DNA polymerase was not working properly
In some Drosophila species there are genes on the Y chromosome that do not occur on the X chromosome. Imagine that a mutation of one gene on the Y chromosome reduces the size by half of individuals with the mutation. Which of the following statements is accurate with regard to this situation? A. This mutation occurs in all offspring of a male with the mutation. B. This mutation occurs in all male but no female offspring of a male with the mutation. C. This mutation occurs in all offspring of a female with the mutation. D. This mutation occurs in all male but no female offspring of a female with the mutation. E. This mutation occurs in all offspring of both males and females with the mutation.
B. This mutation occurs in all male but no female offspring of a male with the mutation.
Which of the following enzymes is important for relieving the tension in a helix as it unwinds during DNA synthesis? A. Ligase B. Topoisomerase C. Single-strand binding proteins D. Helicase
B. Topoisomerase
In cattle, roan coat color (mixed red and white hairs) occurs in the heterozygous (Rr) offspring of red (RR) and white (rr) homozygotes. Which of the following crosses would produce offspring in the ratio of 1 red:2 roan:1 white? A. white × roan B. roan × roan C. red × white D. ed × roan E. The answer cannot be determined from the information provided.
B. roan × roan
What would be the consequence(s) for DNA synthesis if primase were defective?
Both leading and lagging strand synthesis would be incomplete.
RNA primers required for polymerase to continue synthesis must be present on which strand during DNA synthesis?
Both leading and lagging strands
In an analysis of the nucleotide composition of DNA, which of the following will be found? A. A = C B. A = G and C = T C. A + C = G + T D. G + C= T + A
C. A + C = G + T
Which of the following statements describes the eukaryotic chromosome? A. It is composed of DNA alone. B. Active transcription occurs on heterochromatin but not euchromatin. C. It consists of a single linear molecule of double-stranded DNA plus proteins. D. The nucleosome is its most basic functional subunit E. The number of genes on each chromosome is different in different cell types of an organism.
C. It consists of a single linear molecule of double-stranded DNA plus proteins.
Which of the following statements about the DNA in one of your brain cells is true? A. Each gene lies immediately adjacent to an enhancer B. The majority of genes are likely to be transcribed C. It is the same as the DNA in one of your heart cells D. Many genes are grouped into operon-like clusters E. Most of the DNA codes for protein
C. It is the same as the DNA in one of your heart cells
Which of the following is an important exception to the central dogma of molecular biology? A. DNA is the repository of genetic information in all cells. B. Proteins are responsible for most aspects of the phenotype. C. Many genes code for RNAs that function directly in the cell. D. Messenger RNA is a short-lived "information carrier."
C. Many genes code for RNAs that function directly in the cell.
Which of the following statements about DNA synthesis is true? A. Nucleotides are added in a random fashion to single-stranded DNA. B. DNA polymerase adds dNTP monomers in the 3' to 5' direction. C. Primers are short sequences that allow the initiation of DNA synthesis. D. As DNA polymerase moves along the template strand, each new nucleotide provides a 5' hydroxyl group for the next reaction to occur.
C. Primers are short sequences that allow the initiation of DNA synthesis.
All three domains (Bacteria, Archaea, and Eukarya) follow the same genetic code. Therefore, which of the following statements would most likely be correct? A. There were no mutations following the evolution of the genetic code. B. The genetic code evolved before DNA replaced RNA as the unit of genetic information. C. The genetic code evolved before the different domains diverged. D. The genetic code evolved three times
C. The genetic code evolved before the different domains diverged.
Generally speaking, which of the following mutations would most severely affect the protein coded for by a gene? A. a base substitution at the beginning of the gene B. a base substitution at the end of the gene C. a frameshift deletion at the beginning of the gene D. a frameshift deletion at the end of the gene
C. a frameshift deletion at the beginning of the gene
Which of the enzymes covalently connects segments of DNA? A. helicase B. DNA polymerase III C. ligase D. DNA polymerase I E. primase
C. ligase
In rabbits, black fur (B) is dominant over white (b). You find a nest of black baby rabbits in your backyard. What is their genotype?
Cannot be determined without a test cross
A peptide has the sequence NH2-Phe-Pro-Lys-Gly-Phe-Pro-COOH. Which of the following sequences in the coding strand of the DNA could code for this peptide? A. 5' ACT-TAC-CAT-AAA-CAT-TAC-UGA B. 3' AUG-AAA-GGG-TTT-CCC-AAA-GGG C. 3' UUU-CCC-AAA-GGG-UUU-CCC D. 5' TTT-CCC-AAA-GGG-TTT-CCC E. 5' GGG-AAA-TTT-AAA-CCC-ACT-GGG
D. 5' TTT-CCC-AAA-GGG-TTT-CCC
Which of the enzymes removes the RNA nucleotides from the primer and adds equivalent DNA nucleotides to the 3' end of Okazaki fragments? A. helicase B. DNA polymerase III C. ligase D. DNA polymerase I E. primase
D. DNA polymerase I
Which one of the following is LEAST likely to cause mutations in DNA? A. Ultraviolet radiation from sunlight B. Benzopyrenes from cigarette smoke C. Hydroxyl radicals formed as by-products of aerobic respiration D. Light from an incandescent bulb
D. Light from an incandescent bulb
A white-eyed female Drosophila is crossed with a red-eyed male Drosophila. Which statement below correctly describes the results? A. 25% of the females will have white eyes. B. 25% of the females will have red eyes. C. 50% of the females will have red eyes. D. None of the females will have white eyes. E. None of the females will have red eyes.
D. None of the females will have white eyes.
In humans, blue eyes are inherited as a recessive autosomal trait and color blindness is an X-linked recessive trait. A woman with blue eyes and normal color vision whose father was color-blind marries a man who also has normal color vision. He has brown eyes, but his mother had blue eyes. Which of the following would you expect to be TRUE for their sons? A. Their sons will all have normal color vision and blue eyes. B. One-half of their sons will have normal color vision and brown eyes; one-half of their sons will have normal color vision and blue eyes. C. Their sons will all have normal color vision and brown eyes. D. One-fourth of their sons will be color-blind and have blue eyes, one-fourth of their sons will be color-blind and have brown eyes, one-fourth of their sons will have normal color vision and blue eyes, one-fourth of their sons will have normal color vision and brown eyes. E. One-half of their sons will be color-blind and have blue eyes; one-half of their sons will be color-blind and have brown eyes.
D. One-fourth of their sons will be color-blind and have blue eyes, one-fourth of their sons will be color-blind and have brown eyes, one-fourth of their sons will have normal color vision and blue eyes, one-fourth of their sons will have normal color vision and brown eyes.
Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the operator to the far end of the operon, past the transacetylase (lacA) gene, which of the following would likely occur when the cell is exposed to lactose? A. The repressor protein will no longer be produced. B. The inducer will no longer bind to the repressor. C. The repressor will no longer bind to the operator. D. The structural genes will be transcribed continuously. E. The operon will never be transcribed
D. The structural genes will be transcribed continuously.
Which of the following statements about Okazaki fragments in E. coli is true? A. They are usually 50 to 500 bases long. B. They are sealed together by the action of helicase. C. They are synthesized in the 3' to 5' direction. D. They are formed on the lagging strand of DNA.
D. They are formed on the lagging strand of DNA.
Which of the following is most directly associated with phenotypes? A. DNA B. mRNA C. codons D. proteins
D. proteins
Genotype is to _____ as phenotype is to _____.
DNA base sequence; physical traits that are products of the proteins produced
Suppose you are provided with an actively dividing culture of E. coli bacteria to which radioactive thymine has been added. What would happen if a cell replicates once in the presence of this radioactive base?
DNA in both daughter cells would be radioactive.
The central dogma states that:
DNA is transcribed into an mRNA, which is then translated into a protein
What catalyzes DNA synthesis?
DNA polymerase
Why is the new DNA strand complementary to the 3' to 5' strands assembled in short segments?
DNA polymerase can assemble DNA only in the 5' to 3' direction
If a DNA sequence is altered from TAGCTGA to TAGTGA, what kind of mutation has occurred?
Deletion.
Which of the following mechanisms is (are) used to coordinate the expression of multiple, related genes in eukaryotic cells? A. The genes share a single common enhancer, which allows appropriate activators to turn on their transcription at the same time. B. The genes are organized into large operons, allowing them to be transcribed as a single unit. C. A single repressor is able to turn off several related genes. D. Environmental signals enter the cell and bind directly to promoters E. A specific combination of control elements in each gene's enhancer coordinates the simultaneous activation of the genes.
E. A specific combination of control elements in each gene's enhancer coordinates the simultaneous activation of the genes.
A mother has type A blood and gives birth to a child who is type O. What are the possible genotypes for the father? A. IB, IB B. IB,i C. i, i D. IA, i E. B, C and D are possible
E. B, C and D are possible
For a repressible operon to be transcribed, which of the following must occur? A. A corepressor must be present. B. RNA polymerase and the active repressor must be present. C. RNA polymerase must not occupy the promoter, and the repressor must be inactive. D. RNA polymerase cannot be present, and the repressor must be inactive. E. RNA polymerase must bind to the promoter, and the repressor must be inactive
E. RNA polymerase must bind to the promoter, and the repressor must be inactive
Which of the enzymes synthesizes short segments of RNA? A. helicase B. DNA polymerase III C. ligase D. DNA polymerase I E. primase
E. primase
T/F: A codon is a group of three bases that can specify more than one amino acid.
False
Ciprofloxacin inhibits DNA gyrase, a bacterial topoisomerase that cuts DNA ahead of the replication fork, winds the DNA in a direction that relieves the twists added during DNA synthesis, and then reseals the DNA. In ciprofloxacin-treated bacteria, newly synthesized DNA is found in fragments. Based on this evidence, what activity of DNA gyrase is likely to be inhibited by ciprofloxacin?
Ligase activity
During translation, nucleotide base triplets (codons) in mRNA are read in sequence in the 5' → 3' direction along the mRNA. Amino acids are specified by the string of codons. What amino acid sequence does the following mRNA nucleotide sequence specify? 5′−AUGGCAAGAAAA−3′5′−AUGGCAAGAAAA−3′ Express the sequence of amino acids using the three-letter abbreviations, separated by hyphens (e.g., Met-Ser-Thr-Lys-Gly).
Met-Ala-Arg-Lys
What amino acid sequence does the following DNA nucleotide sequence specify? 3′−TACAGAACGGTA−5′3′−TACAGAACGGTA−5′ Express the sequence of amino acids using the three-letter abbreviations, separated by hyphens (e.g., Met-Ser-His-Lys-Gly).
Met-Ser-Cys-His
What amino acid sequence will be generated, based on the following mRNA codon sequence? 5' AUG-UCU-UCG-UUA-UCC-UUG 3'
Met-Ser-Ser-Leu-Ser-Leu
Which mutation(s) would not change the remainder of the reading frame of a gene sequence that follows the mutation(s)?
One addition and one deletion mutation.
Which part of a deoxynucleoside triphosphate (dNTP) molecule provides the energy for DNA synthesis?
Phosphate groups
what is responsible for catalyzing the formation of an RNA primer?
Primase
What is a major difference between eukaryotic DNA replication and prokaryotic DNA replication
Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have multiple origins of replication
The synthesis of a new strand begins with the synthesis of a(n) _____.
RNA primer complementary to a preexisting DNA strand
In eukaryotic gene expression, the step that most prokaryotes do not use is
RNA processing
A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have _____.
T4 protein and T4 DNA
The codon for serine is UCG. The coding (non-template) strand of the DNA that encoded it is _____, and the anticodon of the tRNA that recognizes it is _______.
TCG, AGC
How does the simple primary and secondary structure of DNA hold the information needed to code for the many features of multicellular organisms?
The base sequence of DNA carries the information needed to code for proteins.
What is the relationship between the nucleotide sequence of a gene and the amino acid sequence of a protein?
The nucleotide sequence of a gene is transcribed into a nucleotide sequence of mRNA, which is read during translation in groups of three nucleotides that specify each amino acid
Consider the following family history: Bob has a genetic condition that affects his skin. Bob's wife, Eleanor, has normal skin. No one in Eleanor's family has ever had the skin condition. Bob and Eleanor have a large family. Of their eleven children, all six of their sons have normal skin, but all five of their daughters have the same skin condition as Bob. Based on Bob and Eleanor's family history, what inheritance pattern does the skin condition most likely follow?
X-linked dominant
Which small-scale mutation would be most likely to have a catastrophic effect on the functioning of a protein?
a base deletion near the start of a gene
A change in the nucleotide sequence of a gene can lead to a change in _______, which can lead to a change in in the amino acid sequence of a protein.
a codon
The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. This results in
a polypeptide missing an amino acid.
In rabbits, black fur (B) is dominant over white (b). You find a white baby rabbit in your backyard. What is its genotype?
bb
The U.S. Centers for Disease Control and Prevention (CDC) recommends that anyone who might have been exposed to anthrax begin treatment with the antibiotic ciprofloxacin, a DNA-synthesis inhibitor. For ciprofloxacin to be useful, it must work
exclusively against bacterial DNA synthesis proteins
Imagine crossing a pea heterozygous at the loci for flower color (white versus purple) and seed color (yellow versus green) with a second pea homozygous for flower color (white) and seed color (yellow). What types of gametes will the first pea produce?
four gamete types: white/yellow, white/green, purple/yellow, purple/green
As DNA replication continues and the replication bubble expands, the parental double helix is unwound and separated into its two component strands. This unwinding and separating of the DNA requires three different types of proteins: helicase, topoisomerase, and single-strand binding proteins.
helicase: - binds at the replication fork - breaks H-bonds between bases topoisomerase: - binds ahead of the replication fork - breaks covalent bonds in DNA backbone single-strand binding protein: - prevents H-bonds between bases - binds after the replication fork
Which strand of DNA is synthesized toward the middle of the replication bubble?
lagging strand
Short segments of newly synthesized DNA are joined into a continuous strand by _____.
ligase
What amino acid sequence will be generated, based on the following mRNA codon sequence? 5' AUG-UCU-UCG-UUA-UCC-UUG 3'
met-ser-ser-leu-ser-leu
Benzopyrene in cigarette smoke binds to DNA and distorts its shape, interfering with DNA replication. Which repair mechanism would most likely be used to repair the damage caused by this chemical?
nucleotide excision repair
Semiconservative replication involves a template. What is the template?
one strand of the DNA molecule
Rats that are the offspring of parents that were raised with poor nutrition have a greater chance of developing disorders similar to type 2 diabetes, regardless of the alleles they inherit. This shows that
patterns of gene expression may be inherited
Which point of gene expression will cause the most rapid change in a protein that controls a particular trait?
post-translational modification
A mutant bacterial cell has a defective aminoacyl-tRNA synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will be that
proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU.
The action of helicase creates _____.
replication forks and replication bubbles
sort the following ten codons into one of the three bins, according to whether they code for a start codon, an in-sequence amino acid, or a stop codon. - AAA - UGC - AUC - UGA - AUG - GCA - ACU - UAG - CAC - UGC
start codon: AUG stop codon: UGA, UAG, UAA amino acid: AAA, UCG, CAC, ACU, GCA, AUC
Transcription of the structural genes in an inducible operon
starts when the pathway's substrate is present.
An old DNA strand is used as a _____ for the assembly of a new DNA strand.
template
The DNA of telomeres has been found to be highly conserved throughout the evolution of eukaryotes. What does this most probably reflect?
that the critical function of telomeres must be maintained
Given the damage caused by UV radiation, the kind of gene affected in those with XP is one whose product is involved with
the ability to excise single-strand damage and replace it.
In the transcription of the DNA below, where would the promoter be located? DNA template strand 5' ------------------------- 3' DNA complementary strand 5' ------------------------- 3'
to the right of the template strand
The process of assembling a polypeptide based on the nucleotide sequence of an mRNA is called:
translation
T/F: Single-stranded DNA molecules are said to be antiparallel when they are lined up next to each other but oriented in opposite directions.
true
