Principles of Biology Exam 4 Practice Questions

Unattached earlobes are a dominant trait. Finn and Maggie both have unattached earlobes but their daughter, Celia, does not. If Finn and Maggie have a second child, what is the probability that this child will have attached earlobes? a. 1/4 b. 1/2 c. 1/8 d. 3/4 e. 1

a. 1/4

Which of the following statements is false? a. Gametes are made by mitosis b. Somatic cells are diploid c. Gametes are haploid cells d. A typical body cell is called a somatic cell e. A zygote is a fertilized egg

a. Gametes are made by mitosis

Which of the following statements regarding mitosis and meiosis is false? a. Mitosis produces daughter cells with half the number of chromosomes as the parent cell b. Meiosis only occurs in the ovaries and testes c. A haploid cell has half the chromosomes of a diploid cell d. A normal human zygote has 46 chromosomes e. All sexual life cycles involve an alteration of diploid and haploid stages

a. Mitosis produces daughter cells with half the number of chromosomes as the parent cell

Consider the following sentence: "The dog did not eat." Which of the following variations of this sentence is most like a reading frame mutation? a. The dod idn ote at b. The did not eat c. The did dog not eat d. The dog did dog did not eat e. The dog dog did not eat

a. The dod idn ote at

You are asked to culture an unidentified sample of animal tissue. You notice that the cells seem to fail to exhibit density-dependent inhibition. The source of this tissue sample is most likely a. a cancer b. a fetal liver c. skin d. a scar e. the sperm-producing tissues of the testis

a. a cancer

Any change in the nucleotide sequence of DNA is called a. a mutation b. an anticodon c. a translation d. an advantage e. a codon

a. a mutation

A transgenic animal is a. an animal containing a gene from a third "parent," which may even be another species b. an animal that is the first of its kind to bear a particular allele c. an animal containing genes from three or more species d. an animal in which a genetic defect has been corrected using recombinant DNA therapy e. an animal containing genes from both its parents

a. an animal containing a gene from a third "parent," which may even be another species

An excess of one type of chromosome in a cell is an example of a. aneuploidy b. autopolyploidy c. crossing over d. nondisjunction e. allopolyploidy

a. aneuploidy

Eukaryotic chromosomes differ from prokaryotic chromosomes in that they a. are housed in a membrane-enclosed nucleus b. are copied immediately after cell division c. are simpler d. include fewer proteins e. are circular in structure

a. are housed in a membrane-enclosed nucleus

The cross AaBb x AaBb is an example of a _____ cross and the results of such crosses led Mendel to propose what we now call the law of _____. a. dihybrid, independent assortment b. test, independent assortment c. self, segregation of genes d. dihybrid, segregation of genes e. test, segregation of genes

a. dihybrid, independent assortment

In the process of human gene cloning using recombinant plasmids, the bacterial plasmid a. functions as a vector b. is the source of the gene to be cloned c. comes from the same organism as the gene of interest d. is cultured inside the human cell, which contains the gene to be cloned e. is used to insert the human gene into the bacterial chromosome

a. functions as a vector

A nonsense mutation a. is a result of a change in a codon for an amino acid in a protein to a stop codon. b. must result from a short mRNA transcript of the gene. c. results in a protein that is truncated from the N-terminal end. d. would likely not affect the activity of a protein. e. would not affect the primary structure of a proteins.

a. is a result of a change in a codon for an amino acid in a protein to a stop codon.

The vast majority of people afflicted with recessive disorders are born to parents who were a. not affected at all by the disease b. subjected to some environmental toxin that caused the disease in their children c. slightly affected by the disease, showing some but not all of the symptoms d. both affected by the disease e. affected by the disease but had subclinical symptoms

a. not affected at all by the disease

How many sex chromosomes are in a human gamete? a. one b. three c. two d. twenty-three e. four

a. one

Loss of function mutations tend to be _____ because half the normal enzyme activity usually _____. a. recessive; is sufficient to produce the wild type phenotype b. dominant; is sufficient to produce the wild type phenotype c. recessive; is not sufficient to produce the wild type phenotype d. dominant; is not sufficient to produce the wild type phenotype e. dominant; yields a phenotype between the homozygous wild type and homozygous mutant

a. recessive; is sufficient to produce the wild type phenotype

When a restriction enzyme makes staggered cuts, the overhangs it generates are called a. sticky ends b. blunt ends c. palindromes d. ligases e. recombinants

a. sticky ends

At the start of mitotic anaphase, a. the centromeres of each chromosome come apart b. homologous chromosomes separate c. the chromatid DNA replicates d. daughter chromosomes begin to move toward opposite poles of the cell e. equivalent and complete collections of chromosomes have reached the two poles

a. the centromeres of each chromosome come apart

All the offspring of a cross between a black-eyed mendelien and an orange-eyed mendelien have black eyes. What is the expected phenotypic ratio of a cross between two orange-eyed mendeliens? a. 3 black-eyed: 1 orange-eyed b. 0 black-eyed: 1 orange-eyed c. 1 black-eyed: 3 orange-eyed d. 1 black-eyes: 0 orange-eyed e. 1 black-eyed: 1 orange-eyed

b. 0 black-eyed: 1 orange-eyed

A true-breeding strain of tall soybean plants is crossed with a true-breeding strain of short soybean plants. All the offspring are short. These offspring are then crossed with each other to create an F2 generation. If the height of soybean plants is due to a single gene, then of 200 F2 plants, ______ should be tall a. 25 b. 50 c. 75 d. 100 e. 150

b. 50

Which of the following would be considered recombinant DNA? a. A DNA molecule that was synthesized in the laboratory from nucleotides b. A DNA molecule constructed in the laboratory, that was derived from bacterial, cattle, and yeast DNA c. The DNA in a butterfly that is the hybrid of two species that mated in the wild d. Both a and b e. Both b and c

b. A DNA molecule, constructed in the laboratory, that was derived from bacterial, cattle, and yeast DNA

The molecules that make up a chromosome are _____ and _____. a. proteins, lipids b. DNA, proteins c. proteins, phospholipids d. DNA, RNA e. nucleotides, nucleosides

b. DNA, proteins

Which of the following statements regarding mitosis and meiosis is false? a. Mitosis provides for growth and tissue repair b. Meiosis provides for asexual reproduction c. In mitosis, the chromosomes replication only once in the preceding interphase d. In meiosis, the chromosomes replicate only once in the preceding interphase e. All the events unique to meiosis occur during meiosis I

b. Meiosis provides for asexual reproduction

Which of the following does not occur during interphase? a. The synthesis of cellular components necessary for mitosis b. The condensation of chromatin c. DNA replication d. The generation of sister chromatids e. None of the above; all occur during interphase

b. The condensation of chromatin

A particular genetic cross in which an individual with a dominant phenotype and an unknown genotype is crossed with an individual known to be homozygous for a recessive trait is referred to as a. filial generation mating b. a test cross c. a dihybrid cross d. a reciprocal cross e. a parental cross

b. a test cross

Different forms of a gene are referred to as a. traits b. alleles c. genomes d. phenotypes e. genotypes

b. alleles

Restriction enzymes a. stop transcription b. cut DNA at specific sites c. bind together strands of DNA d. edit proteins e. bind RNA fragments together

b. cut DNA at specific sites

Two chromosomes in a nucleus that carry loci for the same positions on the chromosome but specify different versions of some traits constitute a pair of a. heterologous chromosomes b. homologous chromosomes c. parallel chromosomes d. polyploid chromosomes e. complementary chromosomes

b. homologous chromosomes

All of 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. codominant b. incompletely dominant c. pleiotropic d. recessive e. dominant

b. incompletely dominant

A plasmid a. is the bacterial genome b. is a similar circular piece of non-chromosomal DNA c. is only recombinant d. does not code for proteins e. is double-stranded RNA

b. is a similar circular piece of non-chromosomal DNA

The genetic disease blue sclera is determined by an autosomal dominant allele. The eyes of individuals with this allele have bluish sclera. These same individuals may also suffer from fragile bones and deafness. This is an examples of a. incomplete dominance b. pleiotropy c. epistasis d. codominance e. linkage

b. pleiotropy

Incomplete dominance a. is the same as codominance b. results in a phenotypic ratio of 1:2:1 in a monohybrid cross c. occurs only in X-linked genes d. is far less common than complete dominance e. involves the district expression of both alleles, as in the ABO blood group system

b. results in a phenotypic ratio of 1:2:1 in a monohybrid cross

Prior to mitosis, each chromosome of a eukaryotic cell consists of a pair of a. chromatin b. sister chromatids c. nucleoli d. DNA transcripts e. sister chromosomes

b. sister chromatids

In multicellular organisms a. somatic mutations are passed to offspring by sexual reproduction. b. somatic mutations may be passed to daughter cells by mitosis. c. all mutations produce phenotypic changes. d. meiosis is not required for the transmission of germ line mutations to the next generation. e. all mutations are point mutations.

b. somatic mutations may be passed to daughter cells by mitosis

In human, XO individuals are usually a. fertile females b. sterile females c. monoecious d. fertile males e. sterile males

b. sterile females

The cell cycle control system is most like a. a row of dominoes falling down, each one triggering the fall of the next b. the control device of an automatic mashing machine c. an orchestra director by a conductor d. a light switch turning on a set of room lights e. a video game controller

b. the control device of an automatic washing machine

Epistasis refers to a. the expression of two alleles of the same gene in an individual b. the expression of one gene affecting the expression of another c. the linear order of genes on a chromosome d. intermediate dominance e. a group of genes that are close together

b. the expression of one gene affecting the expression of another

Frame-shift mutations occur a. with all insertions, but not with deletions b. with all insertions and deletions whose sizes are not multiples of three nucleotides c. with all insertions and deletions d. with all insertions and deletions whose sizes are multiples of three nucleotides e. with all deletions, but not with insertions

b. with all insertions and deletions whose sizes are not multiples of three nucleotides

Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form of deafness. Deafness is a recessive trait that is associated with the abnormal allele d. The normal allele at this locus, associated with normal hearing, is D. Dr. Smith's parents could have which of the following genotypes? a. DD and DD b. Dd and DD c. Dd and Dd d. DD and dd e. dd and dd

c. Dd and Dd

Which of the following statements regarding genetic diversity is false? a. Genetic diversity is enhanced by random fertilization b. Genetic diversity is enhanced by independent orientation of chromosomes at metaphase c. Genetic diversity is enhanced by mitosis of somatic cells d. Genetic diversity is enhanced by crossing over during prophase I of meiosis e. Genetic diversity is enhanced by random mutations of the DNA

c. Genetic diversity is enhanced by mitosis of somatic cells

Which of the following is false? a. In animals, cell division is required for growth b. In plants, cell division is required for growth c. In prokaryotes, cell division is required for growth d. In animals, cell division is needed to replace wounded cells e. In animals, cell division is needed for reproduction

c. In prokaryotes, cell division is required for growth

Which of the following features likely accounts for the difference between plant and animal cell cytokinesis? a. Plant and animal cells do not have a common ancestor b. Plant cells have two sets of chromosomes; animal cells have one set of chromosomes c. Plant cell division must maintain the integrity of the cell wall d. Animal cells lack chloroplasts e. Animal cells lack the microfilaments required for forming a cleavage furrow

c. Plant cell division must maintain the integrity of the cell wall

E. coli makes insulin because a. It picked up the insulin gene from another cell b. It needs to regulate its cell-glucose level c. The insulin gene was inserted into it d. It's an ancient gene that now has no function e. No reason, it doesn't make insulin

c. The insulin gene was inserted into it

Which of the following is a difference between PCR and DNA replication in the cell? a. The use of an oligonucleotide primer b. The use of a template strand c. The number of copies produced d. The use of DNA polymerase e. The use of complementary nucleotides in building the copy

c. The number of copies produced

The sex chromosome complement of a normal human male is a. XO b. XX c. XY d. YY e. YO

c. XY

White eyes are a recessive sex-linked trait in Drosophila. If a white-eyed female fly is mated to a red-eyed male, their offspring should be a. males that are 50 percent red-eyed and 50 percent white-eyed, and females that are all red-eyed b. all white-eyed females and all red-eyed males c. all white-eyed males and all red-eyed females d. 50 percent red-eyed and 50 percent white-eyed for both sexes e. all white-eyed for both sexes

c. all white-eyed males and all red-eyed females

The creation of offspring carrying genetic information from a single parent is called a. a life cycle b. sexual reproduction c. asexual reproduction d. regeneration e. spontaneous generation

c. asexual reproduction

The advantage of being able to clone the gene for human insulin is that a. human insulin is more viable than other sources of insulin, so cloning provides a greater chance of obtaining a form that can be used by diabetic's muscles b. there are too few cows, pigs and horses to provide an adequate supply of their insulin c. human insulin is less likely to provoke an allergic reaction than cow, pig, or horse insulin d. cow, pig, or horse insulin cannot keep a diabetic alive for more than three months e. using human insulin increases the probability that, in the future, the person suffering from diabetes can be weaned from a dependence on insulin

c. human insulin is less likely to provoke an allergic reaction than cow, pig, or horse insulin

True-breeding plants a. result from a dihybrid cross b. result from crossing over during prophase I of meiosis c. produce the same offspring when crossed for many generations d. have no mutations e. result from a monohybrid cross

c. produce the same offspring when crossed for many generations

Because of the redundancy in the genetic code, many mutations in the coding regions of genes are a. somatic mutations b. transversions c. silent mutations d. transitions e. inversions

c. silent mutations

The chromosome theory of inheritance states that a. the inheritance pattern of humans is predetermined from chromosomes b. humans have 46 chromosomes c. the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance d. chromosomes that exhibit mutations are the source of genetic variation e. the behavior of chromosomes during mitosis accounts for inheritance patterns

c. the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance

Looking into your microscope, you spot an unusual cell. Instead of the typical rounded cell shape, the cell you see has a very narrow separating two bulging ends. It sort of looks like the number 8. You realize that this cell is a. about to undergo mitosis b. in the G1 phase of interphase c. undergoing cytokinesis d. in the S phase of interphase e. in the G2 phase of interphase

c. undergoing cytokinesis

A biologist is producing many identical copies of the gene that encodes phosphofructokinase. What is the biologist doing? a. Pharming b. Transfecting c. Transforming d. Cloning e. Producing recombinant DNA

d. Cloning

Consider the following sentence: "The dog did not eat." Which of the following variations of this sentence is most like a base substitution mutation? a. The dog did not et. b. The dog dog did not eat. c. The did dog not eat. d. The doe did not eat. e. The dog did not.

d. The doe did not eat

Which of the following statements regarding the flow of genetic information is FALSE? a. Polypeptides form proteins that determine the appearance and function of the cell and organism. b. Eukaryotic mRNA is processed in several ways before export out of the nucleus. c. The codons in a gene specify the amino acid sequence of a polypeptide. d. Transcription occurs in the cytoplasm of eukaryotic cells. e. Ribosomes function as factories that coordinate the functioning of mRNA and tRNA.

d. Transcription occurs in the cytoplasm of eukaryotic cells

A chromosomal mutation that results in a change of gene order on the same chromosome is a. a duplication. b. a reversion. c. a transversion. d. an inversion. e. a translocation.

d. an inversion

The members of a homologous pair of chromosomes a. separate to opposite poles of the cell during mitosis b. are found only in haploid cells c. are present only after the S phase d. are identical in size and appearance e. contain identical genetic information

d. are identical in size and appearance

Which of the following occurs during interphase? a. a reduction in the size of the nuclear membrane b. duplication of the chromosomes c. cytokinesis d. cell growth and duplication of the chromosomes e. separation of newly formed DNA to opposite ends of the cell

d. cell growth and duplication of the chromosomes

Mutations are a. None of the above b. mistakes in the incorporation of amino acids into proteins c. heritable changes in the sequence of DNA bases that produce an observable phenotype d. changes in the nucleotide sequence of DNA that is passed on from one organism to another e. heritable changes in the mRNA of an organism

d. changes in the nucleotide sequence of DNA that is passed on from one organism to another

A person with AB type blood illustrates the principles of a. incomplete dominance b. pleiotropy c. polygenic inheritance d. codominance e. blending inheritance

d. codominance

Due to the phenomenon of dominance a. the same genotype can produce different phenotypes b. different genotypes can give different characters c. the same phenotype can produce different genotypes d. different genotypes can result in the same phenotype e. the same genotype can produce different characters

d. different genotypes can result in the same phenotype

All the offspring of a cross between a black-eyed mendelien and an orange-eyed mendelien have black eyes. This means that the allele for black eyes is _____ the allele for orange eyes a. codominant to b. recessive to c. more aggressive than d. dominant to e. better than

d. dominant to

Mendel's law of independent assortment states that a. chromosomes sort independently of each other during mitosis and meiosis b. genes sort independently of each other in animals but not in plants c. independent sorting of genes produces polyploid plants under some circumstances d. each pair of alleles segregates independently of the other pairs of alleles during gamete formation e. genes are sorted concurrently during gamete formation

d. each pair of alleles segregates independently of the other pairs of alleles during gamete formation

Which of the following is a feature of plant cell division that distinguishes it from animal cell division a. lack of cytokinesis b. production of four (rather than two) new cells per mitotic division c. disappearance and subsequent reappearance of the nucleolus d. formation of a cell plate e. formation of a cleavage furrow

d. formation of a cell plate

A human male carrying an allele for a trait on the X-chromosome is a. heterozygous b. holozygous c. homozygous d. hemizygous e. monozygous

d. hemizygous

Nondisjunction occurs when a. a portion of a chromosome breaks off and is lost b. chromosomes replicate too many times c. two chromosomes fuse into one d. members of a chromosome pair fail to separate e. an entire pair of chromosomes is lost during meiosis I

d. members of a chromosome pair fail to separate

A physical or chemical agent that changes the nucleotide sequence of DNA is called a(n) a. anticodon b. terminator c. reverse transcriptase d. mutagen e. transposon

d. mutagen

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. incomplete dominance b. codominance c. pleiotropy d. polygenic inheritance e. blending inheritance

d. polygenic inheritance

When DNA from two sources is combined into one single piece of DNA, it is known as a. a DNA library b. a vector c. cloned DNA d. recombinant DNA e. a plasmid

d. recombinant DNA

Mutations that are not due to the presence or activity of a mutagen are referred to as _____ mutations. a. conditional b. nonsense c. induced d. spontaneous e. silent

d. spontaneous

When plasmids are used to produced a desired protein, a. the plasmids are inserted into the bacterial chromosomes b. the plasmids multiply and produce the protein outside of the bacterium c. the bacterial chromosome is genetically engineered and the plasmid is used to help the protein replicate d. the digested gene is inserted into the plasmid and the plasmid is inserted into the bacteria via transformation e. the bacterial genome and the plasmid are inserted into the genome of the cell containing the foreign gene (perhaps the cell of a plant or animal)

d. the digested gene is inserted into the plasmid and the plasmid is inserted into the bacteria via transformation

A human gene is inserted into a bacterial cell. This is an example of _____, and the bacterial cell is said to be _____. a. cloning, transfected b. cloning, cloned c. transformation, transfected d. transformation, transgenic e. transformation, cloned

d. transformation, transgenic

In cocker spaniels, black color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s). If the genes are unlinked and the offspring of BBss and bbss individuals are mated with each other, what fraction of their offspring will be black and spotted? a. 1/9 b. 1/16 c. 9/16 d. 3/16 e. 16/16

e. 16/16

Why are some people often more concerned about germ line mutations than somatic ones? a. Germ line mutations are transitions, whereas somatic mutations are transversions b. Germ line mutations affect more nucleotides than somatic mutations do c. Germ line mutations occur more frequently than somatic mutations d. Germ line mutations have phenotypic effects, whereas somatic mutations do not e. Germ line mutations are transmitted to offspring, whereas somatic mutations are not

e. Germ line mutations are transmitted to offspring, whereas somatic mutations are not

Mutations a. are always deleterious b. are of no importance to evolution c. occur at the same rate for all bases d. are always caused by mutagens e. can arise from errors in DNA replication

e. can arise from errors in DNA replication

Which of the following occurs during interphase a. duplication of the chromosomes b. a reduction in the size of the nuclear membrane c. separation of newly formed DNA to opposite ends of the cell d. cytokinesis e. cell growth and duplication of the chromosomes

e. cell growth and duplication of the chromosomes

Genes located close together on the same chromosomes are referred to as _____ genes and generally _____ a. linked, sort independently during meiosis b. codependent, do not sort independently during meiosis c. homologous, are inherited together d. associated, sort independently during meiosis e. linked, do not sort independently during meiosis

e. linked, do not sort independently during meiosis

During which phase of mitosis do the chromosomes line up on a plane equidistant from the two spindle poles? a. telophase b. interphase c. anaphase d. prophase e. metaphase

e. metaphase

Suppose a woman has blood type AB. From this, we can infer that a. her mother was also blood type AB b. her father was type A, and her mother was type B c. her mother was type A, and her father was type B d. her father was also blood type AB e. neither of her parents was type O

e. neither of her parents was type O

DNA ligase binds a. polymerase to the promoter b. an intron to an exon c. introns together d. exons together e. nucleotides together

e. nucleotides together

Pharming is a term that describes a. the use of animals in transgenic research b. plants making genetically altered foods c. synthesis of recombinant drugs by bacteria d. large-scale production of cloned animals e. synthesis of a drug by a transgenic plant or animal

e. synthesis of a drug by a transgenic plant or animal

A base substitution mutation in a gene does not always result in a different protein. Which of the following factors could account for this? a. the fact that the mutation affects only the sequence of the protein's amino acids, so the protein stays the same b. a correcting mechanism that is part of the mRNA molecule c. the double-ring structure of adenine and guanine d. the fact that such mutations are usually accompanied by a complementary deletion e. the fact that some amino acids are specified from more than one codon

e. the fact that some amino acids are specified from more than one codon

Sister chromatids are a. made only of DNA b. formed when chromatids separate during cell division c. found right after a cell divides d. unique to prokaryotes e. tightly linked together at a centromere

e. tightly linked together at a centromere