AP Bio Review 2 Flashcards

The evolution of several species from a single, each occupying a different niche

adaptive radiation

The survival through apparently altruistic behavior of related individuals with common alleles

kin selection

the establishment of a genetically unique population through genetic drift

founder effect

the independent development of similarities between unrelated groups resulting from adaptation to similar environments

convergent evolution

In a non-evolving population, allele frequency remains unchanged from generation to generation.

Hardy Wineburg principle

Sudden reduction of population. Genetic makeup of survivors not representative of original population.

population bottleneck

Natural selection favoring intermediate phenotype. Eliminates the extreme but reduces variation.

Stabilizing selection

Natural selection where frequency shifts to favor one extreme over another, often due to an environment change. Black bear's size helps heat conservation; peppered moths, snails.

directional selection

Natural selection favoring both extremes over intermediate. Small beaks pick up small seeds, large beaks crack thick seeds. May lead to speciation, balanced polymorphism.

disruptive selection

A new species of organism has evolved when

a. the new climate of a population's area has changed greatly

b. a population can no longer interbreed under natural conditions with other closely related organisms

c. variation has occurred within the species due to mutations

d. a population has recently been isolated from the rest of the species by a geographic barrier

e. selection pressures have produced a group of demes

Which of the following contributes LEAST to speciation?

a. sexual reproduction

b. asexual reproduction

c. selection

d. varation

e. isolation

The best evidence that the giant panda is more closely related to bears than is the raccoon-like lesser panda involves

(A) Comparative anatomy
(B) Comparative embryology
(C) DNA sequence comparisons
(D) Behavioral Similarities
(E) Fossil Records

All of the following statements concerning the theory of evolution by natural selection are true EXCEPT:

(A) Organisms produce far more offspring than are required for replacement
(B) The individuals in a population show variation in survivability and in their ability to cope with environmental stress.
(C) The number of offspring that survive to reproduce varies among individuals.
(D) The bodies of organisms in a population change by use and disuse, and the changes are inherited by the next generation.
(E) Some of the variation in adaptation is the result of genetic differences that may be passed on to the next generation

The functional similarity of the mandibles (hinged jaws) of insects and those of mammals is an example of

(A) Homology
(B) Analogy
(C) Divergent evolution
(D) Adaptive radiation
(E) Punctuated equilibrium

Which of the following best summarizes the theory of punctuated equilibrium?

(A) After periods of directional selection, the allelic frequencies in a population will reach equilibrium and then undergo disruptive selection
(B) Most species evolve gradually, with discrete changes appearing in the fossil records at short, regular intervals
(C) Once one species achieves evolutionary dominance, all of the remaining species must compete among themselves for selective advantages; only then will the dominant species be challenged
(D) To ensure survival of the fittest, natural selection eliminates those species that disrupt the balance of nature
(E) Most taxa experience relatively short periods during which they undergo rapid change, followed by relatively long periods during which they undergo relatively little change

In evolutionary terms, which of the following organisms is the most successful

(A) The one that lives the longest
(B) The one that grows most rapidly
(C) The one that leaves the greatest number of offspring that survive to reproduce
(D) The one that has the best characteristics for the the current environment
(E) The one that has the biggest territory

In a population at Hardy-Weinberg equilibrium, which of the following can be predicted or the recessive alleles in the population

(A) They will eventually disappear
(B) They will be selected against
(C) They will be maintained at the same frequency
(D) They will be expressed in the heterozygous condition
(E) They will become dominant

A large assemblage of land snails is subdivided into two populations (A and B) by a river that effectively isolates the two populations for an indefinitely long period. From an evolutionary standpoint, which of the following is the LEAST likely to occur in the two populations?

(A) Population A and B will eventually differ in their ecological requirements
(B) Population A may ultimately breed at a different time of the year than population B does
(C) Population A may undergo instantaneous speciation by the doubling of its chromosome numbers (polyploidy)
(D) Under laboratory conditions, cross fertilization between members of the two populations may be successful even after a long period of geographical separation
(E) The two populations may become morphologically very dissimilar

Evolutionary fitness is measured by

(A) Physical strength
(B) Reproductive success
(C) Length of life
(D) Resistance to disease
(E) Competitiveness

A single substitution in the third position would have the greatest probability of mutational effect on the codon (A) GUU (B) AUU (C) CGU (D) AUG (E) CCC

Which amino acid has the greatest number of codons? (A) Leucine (leu) (B) Proline (pro) (C) Tryptophan (trp) (D) Glutamic acid (glu) (E) Aspartic acid (asp)

Some geneticists consider the third base of a codon to be less important than the first two bases as a code for a specific amino acid. All of the following observations would support this hypothesis EXCEPT:

(A) Any of the bases following a CC_ sequence will position a proline.

(B) Even though the A is replaced by a C, the triplet AGG will still position to an arginine.

(D) An AUU triplet codes for isoleucine, while a UUU triplet codes for phenylalanine.

(E) There are three codons, any of which will position an isoleucine.

The different species of finches on the Galapagos Islands are believed to have arisen as a result of natural selection acting on populations of finches that had experienced
(A) convergent evolution
(B) gene flow
(C) the bottleneck effect
(D) geographic isolation
(E) hybrid sterility

Coat color in mice is determined by genes at two loci. When black mice from a particular population mate, they produce offspring in the following ratios: 9 black: 3 brown: 4 white. These results suggest that white coat color is expressed as a result of
(A) dominance
(B) incomplete dominance
(C) codominance
(D) a sex-linked trait
(E) epistasis

During which of the following time periods could the population have been in Hardy-Weinberg equilibrium for the G locus?
I. 1960-1964
II. 1965-1972
III. 1973-1980

(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III

I and III

Assuming that the population was in Hardy-Weinberg equilibrium for the G locus, what percentage of moths in the natural population was white in 1962?
(A) 2%
(B) 4%
(C) 8%
(D) 20%
(E) 64%

Assuming that the population was in Hardy-Weinberg equilibrium for the G locus, what percentage of the gray moths that emerged in 1980 was heterozygous?
(A) 0%
(B) 25%
(C) 33%
(D) 67%
(E) 100%

67%

Assuming that the population was in Hardy-Weinberg equilibrium for the G locus, what was the frequency of allele G in the gray moths that emerged in 1980?
(A) 0.33
(B) 0.50
(C) 0.67
(D) 0.75
(E) 1.00

0.50

Which of the following is the most likely reason for the observed differences in the frequency of the G allele between 1965 and 1972?
(A) Emigration of white moths from the population
(B) Chance
(C) Selection against gray phenotypes
(D) Speciation
(E) Mutation

A research study sampled populations of field mice annually over the course of 50 years. The population was categorized by coat color. What type of selection is represented?

stabilizing selection

All of the following conditions would result in a change in the frequency of a specific allele in a population EXCEPT
A. Selection against the recessive phenotype
B.Selection against the dominant phenotype
C. Genetic drift
D.Random mating in a large population
E. Mutation of the dominant allel to the recessive allele.

In a populaton that is in Hardy-Weingber equilibrium, the frequence of a recessive allele for a certain hereditary trati is 0.20.
What percentage of the individuals in the next generation would be expected to show the dominant trait.?

96%

In a certain flock of sheep, 4% of the population has black wool and 96% has white wool. Assume that the population is in Hardy Weinberg equilibrium.

If the black wool is a recessive trait, what pecentage of the population is heterozygous for this trait?

32%

In a small group of people living in a remote area, ther is a hgihg incidence of "blue skin", a condition that results from a variation oin the structure of hemoglobin.
All of the "blue skinned" residents can trace their ancestry to one coupl, who were among the original settlers of this region.
The unusually high frequency of "blue skin" in the area is an example of ...

genetic drift

Whichy of the following principles is NOT part of DARWIN'S contributions to the theory of evolution by natural selection?
A. Evolution is a gradual process that occurs over long periods of time.
B. Variation occurs among individuals in a population.
C. Mutations are the ultimate source of genetic variation.
D. More individuals are born than will survive.
E. Individuals that posses the most favorable variations have the best chance of reproducing.

If the population is in Hardy-Weingberg equilibrium, which of the following can be predicted for the recessive allaeles in the population?
A. They will eventually disappear.
B. THey will be selected against.
C. They will be maintained at the same frequency.
D. They will be expressed in the heterozygous conditions.
E. They will become dominant.

Toads in a particular population vary in size. A scientist observes that in this population, large males mate with females significantly more often than small males do. All the following are plausible hypotheses to explain this observation EXCEPT:
(A) Females select large males more often than they select small males as mates.
(B) Small females are more likely to mate with small males and large females are more likely to mate with large males.
(C) Large males are successful in competing for mates more often than small males are.
(D) Large males occupy more breeding territory than small males do.
(E) The calls produced by large males are more attractive to females than the calls made by small males.

The introduction of antibiotics such as penicillin several years ago was immediately effective in
combating infections caused by Staphylococcus. In 1958, however, there were several outbreaks of
staphylococcal infections. People with the infections did not respond to treatment with any of the
antibiotics and there was a large number of deaths. The best explanation for this situation is that

(A) the bacteria reproduced in hosts that were not contaminated with antibiotics
(B) the bacteria from other hosts such as birds, cats, and dogs migrated into human hosts
(C) the bacteria exposed to nonlethal doses of antibiotics quickly learned to avoid them
(D) each generation of bacteria acquired the ability to use antibiotics as nutrients
(E) antibiotic-resistant bacteria survived and multiplied, and these were the forms causing the
infections

The external similarity of dolphins to sharks is an example of
(A) convergent evolution
(B) divergent evolution
(C) behavioral isolation
(D) geographic isolation
(E) adaptive radiation

Which of the following statements concerning viruses is FALSE?
A) Viruses never contain both DNA and RNA.
B) Viruses enter a cell to complete the replication they have begun extracellularly.
C) Some viruses have an outer membrane called an envelope.
D) Viral capsids can assume one of three basic shapes.
E) Tobacco mosaic virus was the first virus to be discovered and characterized

Which statement concerning viruses is NOT true?

a. some viruses contain both single stranded DNA and RNA

b. some viruses may contain single stranded RNA

c. some viruses contain an enzyme-reverse transcriptase

d. some viruses may contain double-stranded DNA

e. some viruses contain double stranded RNA

The best evidence that the giant panda is more closely related to bears than is the racoonlike lesser panda involves
A. comparative anatomy
B. comparative embryology
C. DNA sequence comparisons
D. behavioral similarities
E. fossil records

All of the following statements concerning the theory of evolution by natural selection are true EXCEPT:
A) Organisms produce far more offspring that required for replacement.
B) The individuals in a population show variation in survivability and in their ability to cope with environmental stress.
C) The number of offspring that survive to reproduce varies among individuals.
D) The bodies of organisms in a population change by use and disuse, and the changes are inherited by the next generation.
E) Some of the variation in adaptation is the result of genetic differences that may be passed on to the next generation.

12. Which discovery provides the best evidence to support the belief that
DNA carries genetic information? (1.) Heritable transformation of bacterial
cells is brought about by DNA. (2.) The DNA content from cells of different
tissues of an organism is the same. (3.) The adenine to thymine and guanine
to cytosine ratios in DNA are equal to 1. (4.) DNA is present in
chromosomes. (5.) DNA is present in all cells that divide.

Which of the following statements is\are TRUE?
a. Transport proteins change their shape when they bind a molecule.
b. All molecules will require a transport protein to cross the plasma membrane.
c. Transport proteins always require an energy boost to assist the passage of a molecule from one side of the membrane to the opposite side of the membrane.
d. all of the above

Which of the following statements is\are TRUE?
a. Transcription is slowed when general transcription factors bind to the TATA box.
b. Transcription often involves proteins binding to an enhancer sequence.
c. the first nucleotide to be transcribed is usually positioned just a couple of base pairs form the TATA box.
d. Inducible genes are transcribed all the time.
e. three of the above

Which one of the following statements about viruses is incorrect?
A. Most viruses use cellular machinery to replicate their genetic material.
B. The genomes of viruses are enclosed in a protein coat and occasionally a lipid bilayer envelope.
C. Viruses possess the ability to harness energy from the environment.
D. Viruses are valuable tools in biological research.
E. Some types of viruses employ replicative cycles involving the integration of their genomes into the genome of the host organism.

Which of the following is true of DNA?
A. The nucleotides in one strand are connected by hydrogen bonds.
B. A phosphate group in a nucleotide is attached to the 3′ carbon in ribose.
C. A purine always forms a complementary base pair with a pyrimidine.
D. The percentage of the purine A always equals the percentage of the purine G.
E. It is used by ribosomes for translation.

Which of the following statements is TRUE concerning t-RNA?

A. it weighs more than m-RNA
B. At least one form exists for each amino acid
C. At least one "molecular species" exists for combining with all naturally occurring forms of amino acids
E. it is an enzyme needed to form proteins

May contain the four bases adenine, cytocine, thymine, and guanine

A. DNA molecules only

B. RNA molecules

C. Both DNA and RNA molecules

D. Neither DNA nor RNA molecules

E. Transfer RNA only

Is (are) present in the nucleus of the cell

A. DNA molecules only

B. RNA molecules

C. Both DNA and RNA molecules

D. Neither DNA nor RNA molecules

E. Transfer RNA only

Consists(s) of chains of nucleotides

A. DNA molecules only

B. RNA molecules

C. Both DNA and RNA molecules

D. Neither DNA nor RNA molecules

E. Transfer RNA only

Convey(s) genetic information from the nucleus to the ribosomes

A. DNA molecules only

B. RNA molecules

C. Both DNA and RNA molecules

D. Neither DNA nor RNA molecules

E. Transfer RNA only

non coding segments of DNA interspersed between the coding segments

introns

a segment of a DNA or RNA molecule containing information coding for a protein or peptide sequence.

exons

the haploid set of chromosomes in a gamete or microorganism, or in each cell of a multicellular organism.

genome

a structural unit of a eukaryotic chromosome, consisting of a length of DNA coiled around a core of histones.

nucleosomes

A molecule that increases enzyme activity or a protein that increases the production of a gene product in DNA replication.

activator

A sequence of three adjacent nucleotides, binds complementary nucleotides during translation phase during protein synthesis

anticodon

One can infer from these data that

(A) the data reported for adenine, guanine,. cytosine, and thymine represent their relative percentages in the DNA of the cell

(B) the DNA was extracted from the cell nuclei with an ultracentrifuge

(D) inasmuch as the sums of the relative amounts of the molecular components are not always 100%, the data from this experiment are not valid (E) the DNA of some of the cell nuclei is in the form of a single helix

Which of the following conclusions CANNOT be drawn from the data?

(A) The amount of guanine is about equal to the amount of cytosine in human liver and thymus cells.

(B) The total amount of sugar and phosphate in the DNA molecule is approximately equal to the total amount of purines and pyrimidines.

(D) Guanine represents about one-fifth of the total purine and pyrimidine content of DNA.

(E) The highest amount of adenine is found in the nucleus of T2 bacteriophage.

Which of the following statements is NOT justified by the data?

(A) The amounts of adenine and thymine in any of the nuclei are approximately equal.

(B) The relative amounts of sugar and phosphate are nearly constant regardless of the type of cell studied.

(C) The DNA of human thymus cells has approximately the same content of guanine and cytosine as the DNA of human liver cells.

(D) Adenine, thymine, cytosine, and guanine have different arrangements within the DNA molecule in yeast cells from that in T2 bacteriophage.

(E) The amount of guanine plus cytosine in T2 bacteriophage is about half the amount of the adenine plus thymine.

Arctic foxes typically have a white coat in the winter. In summer, when there is no snow on the ground, the foxes typically have a darker coat. Which of the following is most likely responsible for the seasonal change in coat color?

(A) The decrease in the amount of daylight in winter causes a change in gene expression, which results in the foxes growing a lighter- appearing coat.

(B) The diet of the foxes in summer lacks a particular nutrient, which causes the foxes to lose their white coat and grow a darker- colored coat.

(C) Competition for mates in the spring causes each fox to increase its camouflage with the environment by producing a darker- appearing coat.

(D) The lower temperatures in winter denature the pigment molecules in the arctic fox coat, causing the coat to become lighter in color.

Which of the following is NOT found in every nucleic acid?
a. ribose
b. a phosphate group
c. a single-ring base
d. a double-ring base
e. nitrogen

Testosterone oxido-reductase is a liver enzyme that regulates testosterone levels in alligators. One study compared testosterone oxido-reductase activity between male and female alligators from Lake Woodruff, a relatively pristine environment, and from Lake Apopka, an area that has suffered severe contamination. The graph above depicts the findings of the study. The data in the graph best support which of the following claims?

a. Environmental contamination elevates total testosterone oxido-reductase activity in females.
b. Environmental contamination reduces total testosterone oxido-reductase activity in females.
c. Environmental contamination elevates total testosterone oxido-reductase activity in males.

The bones of a human arm are homologous to structures in all of the following EXCEPT a
(A) whale flipper
(B) batwing
(C) butterfly wing
(D) bird wing
(E) frog forelimb

Which of the following features of angiosperms has probably contributed most to their evolutionary success relative to all other land plant groups?
(A) Phloem
(B) Cutinized aerial surfaces
(C) Flowers and fruits
(D) True leaves and roots
(E) Xylem

The wing of a bat, the flipper of a whale, and the forelimb of a horse appear very different, yet detailed studies reveal the presence of the same basic bone pattern. These structures are examples of
(A) analogous structures
(B) homologous structures
(C) vestigial structures
(D) balanced polymorphism (E) convergent evolution

B

Homologous: it's when very different animals have bones that appear very similar in form or function and seem to be related

Analogous: Species may also have similar traits even though they are not related to each other.

EX: Animals such as penguins and fish both have fin-like structures to help them navigate through their aquatic environments

Although the seal and the penguin both have streamlined, fishlike bodies with a layer of insulating fat, they are not closely related. This similarity results from
(A) convergent evolution
(B) adaptiveradiation
(C) homologous evolution
(D) coevolution
(E) parallel evolution

Which of the following is probably the best explanation for the fact that Antarctica penguins cannot fly, although there is evidence that millions of years ago their ancestors could do so?
(A) Penguins live on land and feed in the water; therefore they have no need to fly.
(B) The Antarctic home of penguins is flat and barren; therefore there is no place to fly.
(C) Ancestral penguins without large wings were better able to swim and feed in the water; therefore, they passed their genes for shorter wing structure on to
their offspring
(D) Ancestral penguins did not use their wings for long periods of time; therefore
today's penguins have only tiny, nonfunctional wings.
(E) The cold and wind of Antarctica make flight impossible; therefore penguins that
live there have lost the ability to fly.

4. The external similarity of dolphins to sharks is an example of
(A) convergent evolution
(B) divergent evolution
(C) behavioral isolation
(D) geographic isolation
(E) adaptive radiation

In a certain flock of sheep, 4% of the population has black wool and 96% has white wool. Assume that the population is in Hardy-Weinberg equilibrium. If black wool is a recessive trait, what percentage of the population is heterozygous for this trait?

32%

In a certain flock of sheep, 4% of the population has black wool and 96% has white wool. Assume that the population is in Hardy-Weinberg equilibrium. What percentage of the population is homozygous for white wool?

64%

In humans, the HIV virus primarily attacks which of the following types of cells?
(A) Epidermal cells
(B) Red blood cells
(C) White blood cells
(D) Glial cells
(E) Neurons

white blood cells

A biologist counted 2,500 cells from an embryo on a microscope slide and recorded the following data.

Stage Number of Cells
Prophase 125
Metaphase 50
Anaphase 50
Telophase 25
Interphase 2,250
Total 2,500

If these cells had been dividing randomly, it could be reasonably concluded that
(A) the duration of anaphase is approximately one-half that of telophase
(B) prophase is approximately three times as long as telophase
(C) metaphase is the shortest stage of the cell cycle
(D) interphase is the longest stage of the cell cycle
(E) the chromosomes can first be .seen in prophase

he different species of finches on the Galapagos Islands are believed to have arisen as a result of natural selection acting on populations of finches that had experienced
(A) convergent evolution
(B) gene flow
(C) the bottleneck effect
(D) geographic isolation
(E) hybrid sterility

9) AIDS is caused by the retrovirus HIV, which makes DNA complementary to the viral RNA using
a. RNA polymerase
b. beta-galactosidase
c. RNA synthase
d. ATPase
e. reverse transcriptase

Which of the following best describes why the polymerase chain reaction is a standard technique used in molecular biology research?
A. It uses inexpensive materials and produces perfect results
B. It can purify specific section of a DNA molecule
C. It can produce large amounts of specific DNA sequences
D. It can duplicate the entire human genome
E. It can produce large amounts of mRNA

Certain metabolic pathways are affected by the buildup of a product which interacts with
an enzyme catalyzing one of the initial steps of the pathway; this can be an example of
(A) transcriptional regulation
(B) thermodynamic regulation
(C) translational regulation
(D) feedback inhibition
(E) posttranslational modification

Which of the following can be diagnosed by examining a karyotype of an individual's
white blood cells?
(A) Sickle cell anemia
(B) Alzheimer disease
(C) Down syndrome
(D) Cystic fibrosis
(E) Duchenne muscular dystrophy

A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.
111. The rate of migration of the DNA fragments through the agarose gel is determined by the
(A) ratio of adenine to cytosine in the fragment
(B) presence of hydrogen bonds between base pairs
(C) length of time the electrophoresis unit is allowed to operate
(D) number of nucleotides in the fragment
(E) volume of the starting sample

A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.

112. Which of the following is true of the dye used to stain the fragments?

(A) It increases the contrast between the agar and the DNA fragments.
(B) It must be accounted for when calculating the molecular weight of the fragments.
(C) Its charged areas interfere with the migration of the DNA.
(D) It is bonded only to the sticky ends of the fragments and can directly determine the sequence of the DNA fragments.
(E) It gives a three-dimensional view of the structure of the DNA fragments.(A) they influence the rate of migration of the fragmentsA student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.

A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.

113. The type and density of the gel are important because
(A) they influence the rate of migration of the fragments
(B) they may cause some DNA molecules to replicate
(C) some DNA nucleotides may be lost due to chemical reactions with the gel
(D) some DNA molecules may sink to the bottom and not migrate
(E) some DNA molecules may cross-link

A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.

114. The procedures described can be used to do all of the following EXCEPT
(A) isolate and purify certain DNA fragments
(B) synthesize novel DNA molecules
(C) study the activity of restriction enzymes
(D) calculate the size of DNA fragments
(E) identify the source of DNA material

.In the 1940's, Avery, MacCleod, and McCarty transformed nonencapsulated bacteria into
encapsulated forms by growing the nonencapsulated cells in a culture containing an
extract made from dead encapsulated cells. The transformed cells produced colonies of
encapsulated bacteria. Three different procedures and their results are outlined below.
Procedure I:
Exact made from dead encapsulated cells added to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure II:
Extract made from dead encapsulated cells treated with protein-degrading enzymes
before adding exact to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure III:
Extract made from dead encapsulated cells treated with DNAse (an enzyme that
selectively destroys DNA) before adding extract to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Only nonencapsulated bacteria grow.
A reasonable conclusion to draw from the results of the experiment is that
(A) DNA is the genetic material
(B) DNA replication is semiconservative
(C) DNA is a double helix
(D) DNA is translated into protein
(E) Mutation is a change in the genetic materialA

In the 1940's, Avery, MacCleod, and McCarty transformed nonencapsulated bacteria into
encapsulated forms by growing the nonencapsulated cells in a culture containing an
extract made from dead encapsulated cells. The transformed cells produced colonies of
encapsulated bacteria. Three different procedures and their results are outlined below.
Procedure I:
Exact made from dead encapsulated cells added to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure II:
Extract made from dead encapsulated cells treated with protein-degrading enzymes
before adding exact to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure III:
Extract made from dead encapsulated cells treated with DNAse (an enzyme that
selectively destroys DNA) before adding extract to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Only nonencapsulated bacteria grow.
What was the purpose of treating the extract with protein-degrading enzymes in
Procedure II ?
(A) To demonstrate that the transforming factor is an enzyme
(B) To demonstrate that the transforming factor is not a protein
(C) To destroy nucleic acids in the exact
(D) To destroy any capsules in the exact
(E) To prevent the extract from being contaminated by nonencapsulated bacteria

In the 1940's, Avery, MacCleod, and McCarty transformed nonencapsulated bacteria into
encapsulated forms by growing the nonencapsulated cells in a culture containing an
extract made from dead encapsulated cells. The transformed cells produced colonies of
encapsulated bacteria. Three different procedures and their results are outlined below.
Procedure I:
Exact made from dead encapsulated cells added to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure II:
Extract made from dead encapsulated cells treated with protein-degrading enzymes
before adding exact to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Both nonencapsulated and encapsulated bacteria grow.
Procedure III:
Extract made from dead encapsulated cells treated with DNAse (an enzyme that
selectively destroys DNA) before adding extract to culture medium.
Nonencapsulated bacteria added to culture medium.
Results: Only nonencapsulated bacteria grow.
What was the purpose of treating the extract with DNAse in Procedure III ?
(A) To remove the encapsulated bacteria from the extract
(B) To serve as a positive control by demonstrating that a protein in the extract is the
transforming factor
(C) To serve as a negative control by demonstrating that transformation does not
occur without DNA
(D) To destroy any enzymes in the extract
(E) To destroy any capsules that might be in the extractC

Which of the following exist as RNA surrounded by a protein coat?
A. Retrovirus
B. prion
C. Prokaryote
D. Spirochete
E. streptococcus

. transcription
B. Translation
C. Transformation
D. Replication
E. Reverse transcription
Process in which a protein is assembled at a ribosome

A. transcription
B. Translation
C. Transformation
D. Replication
E. Reverse transcription
Process in which naked DNA is taken up by a bacterial or yeast Cel

A. transcription
B. Translation
C. Transformation
D. Replication
E. Reverse transcription
Process that results in the prodcution of cDNA from an RNA molecule

A. transcription
B. Translation
C. Transformation
D. Replication
E. Reverse transcription
Process in which RNA is produced by using a DNA

Enzyme used in the synthesis of mRNA

a. DNA ligase

b. DNA polyerase

c. RNA polymerase

d. Nuclease

e. single-strand binding protein

Enzyme used during replication to attach Okazaki fragments to each other

a. DNA ligase

b. DNA polyerase

c. RNA polymerase

d. Nuclease

e. single-strand binding protein

Enzyme that removes damaged DNA to have it replaced with new DNA

a. DNA ligase

b. DNA polyerase

c. RNA polymerase

d. Nuclease

e. single-strand binding protein

100

Enzyme used to position nucleotides during DNA replication

a. DNA ligase

b. DNA polyerase

c. RNA polymerase

d. Nuclease

e. single-strand binding protein

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