BIO – Chapter 12 and 13 Practice Test

Which bacteria killed the mice in Griffith’s transformation experiment?
a. live, harmless bacteria and heat-killed, harmful bacteria
b. live, harmless bacteria and heat-killed, harmless bacteria
c. live harmful bacteria and heat-killed, harmless bacteria
d. live harmless bacteria, and live, harmful bacteria
a. live, harmless bacteria and heat-killed, harmful bacteria

Griffith called the process he observed transformation because
a. the mouse had been transformed.
b. the harmful bacteria had been transformed.
c. the harmless bacteria had been transformed.
d. the experiment had been transformed.
c. the harmless bacteria had been transformed.

What did Avery conclude caused transformation?
b. A protein was the transforming factor.
c. A carbohydrate was the transforming factor.
d. A lipid was the transforming factor.
a. DNA was the transforming factor.

What happened when Griffith injected mice with the harmless, R-strain bacteria alone?
a. The bacteria transformed.
b. The mouse lived.
c. The mouse died.
d. The bacteria died.
b. The mouse lived.

What would have happened if Avery had added an enzyme that digested all the nucleic acids to the mixture of heat-killed bacteria, added the mixture to harmless bacteria, and injected the mixture into mice?
a. The harmless bacteria would have been transformed, and the mice would have died.
b. The harmless bacteria would not have been transformed, and the mice would have lived.
c. The harmless bacteria would not have been transformed, and the mice would have died.
d. The harmless bacteria would have been transformed, and the mice would have lived.
b. The harmless bacteria would not have been transformed, and the mice would have lived.

What property of DNA does bacterial transformation illustrate?
a. Bacterial DNA cannot move into other bacteria and function.
b. Bacterial DNA can move into another bacteria and function.
c. Bacterial DNA uses four nucleotides bases that work in pairs.
d. Bacterial DNA is found in a circular chromosome.
b. Bacterial DNA can move into another bacteria and function.

Griffith’s experiments advanced the study of genetics by proving that
a. there is a chemical that contains genetic information that can be passed from one organism to another.
b. bacteria can make people sick by infecting them with a chemical that contains genetic information.
c. the bacteria that can make mice sick are the same bacteria that can be grown in culture dishes in a laboratory.
d. genetic information can be passed from parents to their offspring during sexual reproduction.
a. there is a chemical that contains genetic information that can be passed from one organism to another.

What is inside a bacteriophage?
a. protein
b. nucleic acid
c. lipid
d. carbohydrate
b. nucleic acid

What do bacteriophages infect?
a. mice.
b. humans.
c. viruses.
d. bacteria.
d. bacteria.

Why did Hershey and Chase label the viral DNA with radioactive phosphorous and not radioactive sulfur?
a. DNA contains phosphorus and no sulfur.
b. Proteins contain phosphorus and no sulfur
c. DNA contains sulfur and little phosphorous.
d. Proteins acids contain sulfur and little phosphorous.
a. DNA contains phosphorus and no sulfur.

What stores information in a cell?
a. proteins
b. carbohydrates
c. lipids
d. DNA
d. DNA

What happens when a piece of DNA is missing?
a. Genetic information is stored.
b. Genetic information is copied.
c. Genetic information is lost
d. Genetic information is transmitted.
c. Genetic information is lost

In what way is DNA like a book?
a. DNA has information organized with an kind of index.
b. DNA has stored information, that can be copied and passed on.
c. DNA has information wrapped in an identifying cover,
d. DNA has information that is periodically updated.
b. DNA has stored information, that can be copied and passed on.

In which cells is the accurate transmission of information most important?
a. nerve cells
b. skin cells
c. sex cells
d. bone cells
c. sex cells

Which of the following is a nucleotide found in DNA?
a. adenine + phosphate group + thymine
b. cytosine + phosphate group + guanine
c. deoxyribose + phosphate group + polyrnerase
d. deoxyribose + phosphate group + cytosine
d. deoxyribose + phosphate group + cytosine

Because of base pairing in DNA, the percentage of
a. adenine molecules in DNA is about equal to the percentage of guanine molecules.
b. thymine molecules in DNA is about equal to the percentage of adenine molecules
c. adenine molecules in DNA is much greater than the percentage of thymine molecules.
d. cytosine molecules in DNA is much greater than the percentage of guanine molecules.
b. thymine molecules in DNA is about equal to the percentage of adenine molecules

What structural problem prevents adenine from pairing with guanine?
a. The bases are both short
b. They lack phosphate groups.
c. They lack the deoxyribose group.
d. The bases are both long.
d. The bases are both long.

DNA makes a good molecule for storing information because
a. its bases can be joined together in any order, like the letters of the alphabet can be strung to form different words.
b. each nucleotide within a DNA strand can give a cell different information, and there are many nucleotides in every cell
c. it can absorb ultraviolet light, so DNA can help protect cells from the damaging effects
of this form of radiation.
d. it is a type of nucleic acid, and most acids are an important part of information storage
within cells.
a. its bases can be joined together in any order, like the letters of the alphabet can be strung to form different words.

Which of the following best describes Rosalind Franklin’s contribution to our understanding of the structure
of DNA?
a. She created many models of DNA based on what was known about its properties, and
eventually figured out that the structure of DNA is a double helix,
b. She purified large amounts of DNA, stretched the fibers so the strands were parallel, and used an X-ray beam to produce an image of the molecule.
c. She isolated DNA from many different organisms, and discovered that in every sample,
the amount of guanine was almost exactly equal to the amount of cytosine.
d. She used radioactive phosphorus and sulfur to produce radioactive viruses, then allowed
these viruses to infect bacteria. She found that DNA was the transforming material.
b. She purified large amounts of DNA, stretched the fibers so the strands were parallel, and used an X-ray beam to produce an image of the molecule.

Rosalind Franklin contributed to the understanding of DNA by
a. producing images ofDNA molecules using X-rays.
b. figuring out that DNA strands form a double helix.
c. conducting experiments that showed which nucleotides are complementary.
d. finding that DNA was nucleic acid made up of a long chain of individual nucleotides
a. producing images ofDNA molecules using X-rays.

Which of the following statements correctly describes Chargaff’s contribution to the study of DNA?
a. Chargaff hypothesized that DNA was a double helix, but he did not produce the image
that proved this fact.
b. Chargaff’s experiments conclusively proved that DNA was made of nucleotides, but he
could not show that there four types of nitrogenous bases.
c. Chargaffs showed that adenine and thymine were found in equal percentages in DNA, but he did not know this was because of base-pairing.
d. Chargaff’s work proved that DNA could be made using radioactive nucleotides, but he
did not show that DNA could be transferred from one organism to another.
c. Chargaffs showed that adenine and thymine were found in equal percentages in DNA, but he did not know this was because of base-pairing.

Which scientist(s) figured out that the shape of a DNA molecule is a double helix?
a. Hershey and Chase
b. Griffith
c. Watson and Crick
d. Franklin
c. Watson and Crick

In the Hershey-Chase experiment, what happened to the bacteria that liad been infected by viruses that had
radioactive DNA, and to the bacteria that had been infected with viruses that had been marked with
radioactive proteins?
a. The bacteria infected with viruses that had radioactive DNA had become radioactive. The bacteria that had been infected with viruses marked with radioactive proteins were not radioactive.
b. The bacteria infected with viruses that had radioactive proteins had become radioactive.
The bacteria that had been infected with viruses marked with radioactive DNA were not
radioactive.
c. The bacteria infected with viruses that had radioactive DNA had become radioactive.
The bacteria that had been infected with viruses marked with radioactive proteins had
also became radioactive.
d. The bacteria infected with viruses that had radioactive DNA had not become
radioactive. The bacteria that had been infected with viruses marked with radioactive
proteins had also not become radioactive.
a. The bacteria infected with viruses that had radioactive DNA had become radioactive. The bacteria that had been infected with viruses marked with radioactive proteins were not radioactive.

Which scientist made x-ray diffraction photos of DNA?
a. Franklin
b. Chargaff
c. Watson
d. Avery
a. Franklin

What is the chronological order of the important discoveries in the structure of DNA?
a. Franklin makes an X-ray diffraction photo of DNA -* Chargaff’ s ratios of nucleotides -+
Watson and Crick identify the double helix
b. Franklin makes an X-ray diffraction photo of DNA – Watson and Crick identify the
double helix-> Chargaff’ s ratios of nucleotides
c. Chargaff’ s ratios of nucleotides -> Watson and Crick identify the double helix-> Franklin makes an X-ray diffraction photo of DNA
d. Chargaff’s ratios of nucleotides -> Franklin makes an X-ray diffraction photo of DNA -> Watson and Crick identify the double helix
d. Chargaff’s ratios of nucleotides -> Franklin makes an X-ray diffraction photo of DNA -> Watson and Crick identify the double helix

Which of the following forms a base pair with thymine?
a. deoxyribose
b. adenine
c.guanine
d. cytosine
b. adenine

What did Rosalind Franklin contribute to the effort to identify the structure of DNA?
a. models made of cardboard and wire showing the shape of DNA
b. the ratios of the two sets of nucleotide pairs in DNA
c. radioactive evidence that DNA carried the genetic code
d. x-ray diffraction photos of the DNA molecule
d. x-ray diffraction photos of the DNA molecule

Watson and Crick discovered the two strands in DNA
a. run in perpendicular directions.
b. run in the same direction.
c. run in opposite directions.
d. run in random directions.
c. run in opposite directions.

DNA replication results in two DNA molecules?
a. each with two new strands.
b. one with two new strands and the other with two original strands.
c. each with one new strand and one original strand.
d. each with two original strands.
c. each with one new strand and one original strand.

During DNA replication, a DNA strand that has the bases CTAGGT produces a strand with the bases
a. TCGAAC.
b. GATCCA
c. AGCTTG.
d. GAUCCA
b. GATCCA

What enzyme works to add DNA to ends of chromosomes in rapidly dividing cells such as those found in an embryo, to prevent genes from being lost during replication?
a. DNA polymerase
b. histones
c. telomerase
d. chromatin
d. chromatin

Which of the following include all the others?
a. DNA molecules
b. histones
c. chromosomes
d. nucleosomes
c. chromosomes

In eukaryotes, DNA
a. is located in the nucleus.
b. floats freely in the cytoplasm.
c. is located in the ribosomes.
d. is circular.
a. is located in the nucleus.

Which would be greater in a eukaryote than in a prokaryote?
a. The percentage of guanine nucleotides,
b. The total number of base pairs in a chromosome.
c. The number of replication forks on a strand of DNA.
d. The total amount of DNA in a cell.
c. The number of replication forks on a strand of DNA.

What binds to the prokaryotic chromosome to start DNA replication?
a. replication forks
b. regulatory proteins
c. chromatids
d. telomeres
b. regulatory proteins

In both prokaryotes and eukaryotes, how many copies of the chromosome are left after replication?
a. I
b. 2
c. 3
d. 4
b. 2

In both prokaryotes and eukaryotes, DNA replication happens
a. before cell division.
b. in the nucleus.
c. only to telomeres.
d. around the histones.
a. before cell division.

RNA contains the sugar
a. ribose.
b. deoxyribose.
c. glucose.
d. lactose.
a. ribose.

Unlike DNA, RNA contains
a. adenine.
b. uracil.
c. phosphate groups.
d. thymine.
b. uracil.

Which of the following are found in both DNA and RNA?
a. ribose, phosphate groups, and adenine
b. deoxyribose, phosphate groups, and guanine
c. phosphate groups, guanine, and cytosine
d. phosphate groups, guanine, and thymine
c. phosphate groups, guanine, and cytosine

Which of the following is true?
a. RNA is usually single-stranded.
b. DNA is usually single-stranded.
c. DNA contains uracil.
d. RNA contains thymine.
a. RNA is usually single-stranded.

Which type of RNA brings the information in the genetic code from the nucleus to other parts of the cell?
a. rRNA
b. tRNA
c. mRNA
d. RNA polymerase
c. mRNA

Which of the following is true of transcription?
a. In eukaryotes, transcription takes place in the cytoplasm and requires many enzymes,
b. RNA polymerase recognizes and binds to specific regions of the DNA called introns
c. RNA editing removes the exons from pre-mRNA, leaving only the introns in the final
molecule.
d. RNA polymerase can make many molecules of RNA from a single DNA sequence.
d. RNA polymerase can make many molecules of RNA from a single DNA sequence.

Which of the following statements is true of eukaryotic DNA?
a. A promoter is part of an intron.
b. An intron is part of a promoter.
c. Introns are sequences of DNA.
d. Exons are edited out of pre-mRNA
c. Introns are sequences of DNA.

Which molecules are involved in protein synthesis?
a. transfer RNA, introns, and mutagens
b. messenger RNA, introns, and ribosomal RNA
c. ribosomal RNA, transfer RNA, and mutagens
d. messenger RNA, ribosomal RNA, and transfer RNA
d. messenger RNA, ribosomal RNA, and transfer RNA

From which molecules are rRNA molecules transcribed?
a. tRNA
b. rRNA
c. DNA
d. proteins
c. DNA

What is produced during transcription?
a. RNA molecules
b. DNA molecules
c. RNA polymerase
d. proteins
a. RNA molecules

During eukaryotic transcription, an RNA molecule is formed that is
a. complementary to both strands of DNA.
b. identical to an entire single strand of DNA.
c. double-stranded and inside the nucleus.
d. complementary to part of one strand of DNA.
d. complementary to part of one strand of DNA.

How many nucleotides are needed to specify three amino acids?
a. 3
b. 6
c. 9
d. 12
c. 9

There are 64 codons and 20 amino acids. Which of the following is true?
a. Several different codons can specify the same amino acid
b. Each codon specifies a different amino acid.
c. Some amino acids have no link to a codon.
d. Each amino acid is specified by only one codon
a. Several different codons can specify the same amino acid

A promoter is a
a. binding site for DNA polymerase.
b. binding site for RNA polymerase.
c. start signal for replication.
d. stop signal for transcription.
b. binding site for RNA polymerase.

What happens during translation?
a. Messenger RNA is made from a DNA code.
b. The cell uses a messenger RNA code to make proteins.
c. Transfer RNA is made from a messenger RNA code.
d. Copies of DNA molecules are made.
b. The cell uses a messenger RNA code to make proteins.

Which of the following terms is LEAST closely related to the others?
a. spindle fiber
b. tRNA
c. polypeptide
d. anticodon
a. spindle fiber

During translation, the type of amino acid that is added to the growing polypeptide depends on the
a. codon on the mRI’A and the anticodon on the rRNA.
b. anticodon on the mRNA and the anticodon on the tRNA
c. anticodon on the rRNA and the codon on the mRNA.
d. codon on the mRNA and the anticodon on the tRNA.
d. codon on the mRNA and the anticodon on the tRNA.

A protein is being assembled when
a. DNA is being translated.
b. RNA is being transcribed.
c. RNA is being translated.
d. DNA is being transcribed.
c. RNA is being translated.

Genes contain instructions for assembling
a. operons.
b. nucleosomes.
c. proteins.
d. mutagens.
c. proteins.

Which is the correct sequence of the transfer of information in most organisms?
a. protein to DNA to RNA
b. RNA to DNA to protein
c. DNA to RNA to protein
d. RNA to protein to DNA
c. DNA to RNA to protein

What is an exception to the central dogma of
molecular biology?
a. Viruses sometimes transfer information from RNA to DNA.
b. Viruses sometimes transfer information from DNA to RNA.
c. Viruses sometimes transfer information from proteins to DNA.
d. Viruses can translate without RNA.
a. Viruses sometimes transfer information from RNA to DNA.

Which of the following best describes the what happens during gene expression?
a. A cell reads the instructions in DNA and builds a protein based on those instructions.
b. A gene is copied many times so that all of a cell’s daughter cells will have their own copy.
c. The nucleus of a cell builds cellular proteins based on the sequence of the mRNA code.
d. A single gene leaves the nucleus of a cell and travels through the cytoplasm to the
membrane.
a. A cell reads the instructions in DNA and builds a protein based on those instructions.

In eukaryotes
a. Transcription takes place in the cytoplasm, and translation takes place in the nucleus.
b. Transcription takes place in the nucleus, and translation takes place in the cytoplasm.
c. Transcription and translation both take place in the nucleus.
d. Transcription and translation both take place in the cytoplasm.
b. Transcription takes place in the nucleus, and translation takes place in the cytoplasm.

A mutation that involves one or a few nucleotides is called
a. a mutagen.
h. an inversion.
c. a point mutation.
d. a translocation.
c. a point mutation.

Which of the following is a chromosomal mutation?
a. inversion
b. insertion
c. point mutation
d. substitution
a. inversion

One difference between a gene mutation and a chromosornal mutation is that
a. A gene mutation affects the DNA of more genes than a chromosomal mutation.
b. A gene mutation can involve a insertion or deletion, but cannot result in a frameshift.
c. A chromosomal mutation can change the number of chromosomes in a cell.
d. A chromosomal mutation is more likely to be passed on to offspring or daughter cells.
c. A chromosomal mutation can change the number of chromosomes in a cell.

When a chromosome undergoes a deletion mutation, information is
a. repeated.
b. lost.
c. reversed.
d. transferred
b. lost.

Most mutations
a. have no effect on an organism.
b. are fatal to an organism.
e. are helpful to an organism.
d. are harmful to an organism.
a. have no effect on an organism.

What are some characteristics of polyploid plants?
a. They tend to be weaker and smaller than diploid plants.
b. They tend to be bigger and stronger than diploid plants.
c. They tend to be weaker, but bigger than diploid plants.
d. They tend to be smaller, but stronger than diploid plants.
b. They tend to be bigger and stronger than diploid plants.

Which of the following statements is true about gene regulation in prokaryotes?
a. Promoters determine whether a gene is expressed.
b. Expressed genes make more DNA.
c. DNA-binding proteins determine whether a gene is expressed.
d. RNA polymerase regulates gene expression.
c. DNA-binding proteins determine whether a gene is expressed.

In E, coli, the lac operon controls the
a. breakdown of lactose.
b. production of lactose.
c. breakdown of glucose.
d. production of glucose
a. breakdown of lactose.

A lac repressor turns OFF the expression of the lac genes by
a. binding to the promoter.
b. DNA polymerase.
c. binding to the operator.
d. binding to the lac genes.
c. binding to the operator.

When E. coli is grown on glucose, and there is no lactose available
a. lactose molecules bind to the lac repressor.
b. the lac repressor binds to the operator of the lac operon.
c. RNA polymerase binds to the promoter of the lac operon.
d. the lac genes are transcribed into messenger RNA.
b. the lac repressor binds to the operator of the lac operon.

Which is involved with the regulation of eukaryotic genes?
a. operon
b. DNA polymerase
c. TATA box
d. operator
c. TATA box

Which of the following is involved in regulating gene expression in prokaryotes, but not in eukaryotes?
a. operon
b. TATA box
c. promoter sequences
d. enhancer sequences
a. operon

Gene regulation in eukaryotes
a. usually involves operons.
b. is simpler than in prokaryotes.
c. allows for cell specialization.
d. includes the action of an operator region
c. allows for cell specialization.

Specialized cells regulate the expression of genes because they
a. do not want the genes to become worn out.
b. cannot control the translation of proteins.
c. do not carry the complete genetic code in their nuclei.
d. do not need the proteins that are specified by certain genes
d. do not need the proteins that are specified by certain genes

What regulates the expression of most eukaryotic genes?
a. mRNA
b. transcription factors
c. dicer enzymes
d. silencing complexes
b. transcription factors

Hox genes determine an animal’s
a. body plan.
b. size.
c. skin color.
d. eye color.
a. body plan.

In a multicellular organism, nerve cells are different from muscle cells because
a. each cell type has a unique set of transcription factors and repressors, so it expresses a specific set of genes.
b. each type of cell within a multicellular organism contains a different set of genes.
c. random events within each cell regulate the expression of genes and result in different
genes being expressed in different cells.
d. cells gain and lose different genes during embryonic development, so each cell in an adult only has some genes from the original set,
a. each cell type has a unique set of transcription factors and repressors, so it expresses a specific set of genes.