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Biology-1
Exam Three
1. The creation of genetically identical offspring by a single parent, without the participation of sperm and egg, is
called
a. asexual reproduction.
b. sexual reproduction.
c. regeneration.
d. spontaneous generation.
2. The need for cells to be in contact with a solid surface to divide is called,
a. growth factor desensitization
b. anchorage dependence
c. cell constraint
d. density-dependent inhibition
e. cell division repression
3. Chromatin is
a. composed of DNA and protein
b. found in the cytoplasm of a cell
c. composed of microfilaments and actin filaments and are part of the cytoskeleton
d. found in the cytoplasm of the cell anchoring organelles
e. none of the above
4. Which of the following statements about human somatic cells is true?
a. has 23 homologous pairs
b. has a total of 46 chromosomes
c. has 2 sex chromosomes
d. is diploid
e. all of the above are true
5. Which of the following statements is false?
a. Gametes are sex cells like sperm and egg
b. Somatic cells are diploid.
c. Gametes are made by meiosis
d. A zygote is a fertilized egg
e. A human zygote is haploid
6. Homologous chromosomes:
a. are genetically identical
b. are similar in length
c. carry information for the same inherited traits
d. are formed during DNA replication
e. b and c are correct
7. Both mitosis and meiosis are preceded by
a. prometaphase.
b. interphase.
c. prophase.
d. telophase.
e. cytokinesis
8. During which stage of meiosis are homologous chromosomes separated?
a. interphase I
b. anaphase I
c. metaphase I
d. interphase II
e. anaphase II
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Biology-1
Exam Three
9. The centrosome is a region in which
a. the nucleus is located prior to mitosis
b. new spindle microtubules form
c. sister chromatids are attached to one another
d. centrioles are located
e. chromosomes are grouped during telophase
10. What is a sister chromatid?
a. a chromosome found outside the nucleus
b. a special region that holds two centromeres together
c. another name for the chromosomes found in genetics
d. a chromosome in G1 of the cell cycle
e. a replicated chromosome
11. 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 I.
c. Genetic diversity is enhanced by mitosis.
d. Genetic diversity is enhanced by crossing over during meiosis.
12. During which phase of the cell cycle would you expect to see chromosomes for the first time in the cell cycle?
a. metaphase
b. prophase
c. telophase
d. anaphase
e. interphase
13. During which phase of mitosis does the nuclear envelope re-form?
a. anaphase
b. metaphase
c. prophase
d. telophase
e. none of the above
14. The creation of genetically identical offspring by a single parent, without the participation of sperm and egg, is
called
a. asexual reproduction
b. sexual reproduction
c. regeneration
d. spontaneous generation
e. fertilization
15. Which of the following variations of the sentence "Where is the cat?" is most like a chromosomal deletion?
a. Where is cat?
b. Where is the the cat?
c. Where the is cat?
d. Where is cat the the cat?
16. You and your lab partner are observing a cell under a microscope, but you do not know whether it is a eukaryote
or a prokaryote. Which of the following observations regarding the chromosomes would you use to immediately
conclude that the cell is a eukaryote?
a. The chromosomes are circular in structure.
b. The chromosomes are housed in a membrane-enclosed nucleus.
c. The chromosomes contain very few proteins.
d. The chromosomes are very simple in structure.
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Biology-1
Exam Three
17. Which of the following statements regarding genetic diversity is false?
a. Genetic diversity increases due to random fertilization.
b. Genetic diversity increases due to independent orientation of chromosomes at metaphase I.
c. Genetic diversity increases by mitosis.
d. Genetic diversity increases by crossing over during meiosis.
e. Genetic diversity increases by recombination
18. A cell that has a cell wall is undergoing cell division, and the following events are observed: the formation of a
cell plate and the division of the cell into two daughter cells. What type of cell is being observed and what
process(es) is it going through?
a. prokaryote; telophase of mitosis
b. animal cell; telophase and cytokinesis of mitosis
c. plant cell; telophase and cytokinesis of mitosis
d. plant cell; telophase II of meiosis
19. All the offspring of a cross between a red-flowered plant and a white-flowered plant have pink flowers. This
means that the allele for red flowers is ________ to the allele for white flowers.
a. dominant
b. codominant
c. incompletely dominant
d. recessive
20. All the offspring of a cross between a purple flower and a white flower have purple flowers. This means that the
allele for purple flower color is ________ the allele for orange eyes.
a. codominant to
b. incompletely dominant to
c. recessive to
d. more aggressive than
e. dominant to
21. Which of the following statements is false?
a. Incomplete dominance supports the blending hypothesis.
b. The four blood types result from various combinations of the three different ABO alleles.
c. ABO blood groups can provide evidence of paternity.
d. The impact of a single gene on more than one character is called pleiotropy.
22. The alleles of a gene are found at ________ chromosomes.
a. the same locus on non-homologous
b. different loci on homologous
c. different loci on non-homologous
d. the same locus on homologous
e. none of the above
23. If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of the cross AaBb × AaBb?
a.
16:0:0:0
b. 8:4:2:2
c.1:1:1:1
d.9:3:3:1
24. Assuming that the probability of having a female child is 1/2 and the probability of having a male child is also
1/2, what is the probability that a couple's first-born child will be female and that their second-born child will be
male? (Use the rule of multiplication to solve)
a. 1/5
b. 1/4
c. 1/2
d. 3/4
e. not enough information
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Biology-1
Exam Three
25. Which of the following is essentially the opposite of pleiotropy?
a. incomplete dominance
b. codominance
c. multiple alleles
d. polygenic inheritance
26. Any gene located on a sex chromosome
a. is called a recessive gene
b. is called a sex-linked gene
c. will exhibit pleiotropy
d. will exhibit codominance
e. is recessive
27. What is the normal makeup of sex chromosomes in a human female?
a. two X chromosomes
b. two Y chromosomes
c. two X chromosomes and one Y chromosome
d. one X chromosome and one Y chromosome
e. one Y chromosome
28. Below are two statements. Which (if any) applies to the law of segregation? Which (if any) applies to the law of
independent assortment?
I: Phenotypes for long tails and big eyes are inherited separately in lab mice.
II: A baby mouse inherits a maternal red eye allele and a paternal black eye allele.
a. A: segregation; B: independent assortment
b. A: independent assortment; B: segregation
c. A: segregation; B: segregation
d. A: independent assortment; B: independent assortment
29. A testcross is
a. a mating between an individual of unknown genotype and an individual homozygous recessive for the
trait of interest.
b. a mating between an individual of unknown genotype and an individual heterozygous for the trait of
interest.
c. a mating between two individuals heterozygous for the trait of interest.
d. a mating between two individuals of unknown genotype.
e. none of the above
30. rs of DNA and RNA are
a. amino acids
b. monosaccharides
c. nucleotides
d. fatty acids.
e. nucleic acids
31. Which of the following statements regarding RNA is false?
a. RNA uses the sugar dextrose.
b. RNA uses the nitrogenous base uracil.
c. One RNA molecule can include four different nucleotides in its structure.
d. RNA molecules have a sugar-phosphate backbone.
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Biology-1
Exam Three
32. Which of the following is true concerning the 3 prime end of one strand of the DNA double helix?
a. The 3 prime carbon is attached to a hydroxyl group
b. The 3 prime carbon is attached to a phosphate group
c. During DNA replication, neither strand grows from the 3 prime end
d. The 3 prime end of one strand is next to (across from) the 3 prime end of the other strand
e. None of the above are true
33. DNA replication
a. occurs through the addition of nucleotides to the 5 prime end of the DNA molecule.
b. results in the formation of four new DNA strands.
c. only involves copying half of the DNA
d. begins when two DNA molecules join together to exchange segments.
e. none of the above
34. Which enzyme is correctly paired with its function?
a. DNA polymerase- transcription
b. RNA polymerase-transcription
c. DNA ligase-translation
d. Helicase-linking fragmented DNA
e. Primase-synthesize (make) new strands of DNA
35. Which of the following enzymes provides a free 3 prime (OH) end by laying down a short RNA sequence for
DNA polymerase to add nucleotides to?
a. helicase
b. primase
c. ligase
d. RNA polymerase
e. DNA polymerase
36. The lagging strand which is formed during DNA replication
a. grows from the 5 prime end
b. is synthesized continuously
c. is synthesized in Okazaki fragments
d. is synthesized toward the replication fork
e. none of the above
37. When one DNA molecule is copied to make two DNA molecules, each new DNA contains
a. none of the parent DNA
b. 25% of the parent DNA
c. 50% of the parent DNA
d. 75% of the parent DNA
e. 100% of the parent DNA
38. How many replication forks exist in two origins of replication?
a. 2 replication forks
b. 4 replication forks
c. 6 replication forks
d. 8 replication forks
e. 12 replication forks
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Biology-1
Exam Three
39. The genetic material is duplicated during
a. the mitotic phase
b. G1
c. the S phase
d. G2
e. cytokinesis
40. Which of the following options best depicts the flow of information when a gene directs the synthesis of a cellular
component?
a. RNA → DNA → RNA → protein
b. DNA → RNA → protein
c. protein → RNA → DNA
d. DNA → tRNA → mRNA → protein
41. Where does translation occur in eukaryotic cells?
a. on the plasma membrane
b. in the nucleus
c. in the cytoplasm
d. in vesicles
e. none of the above
42. A ___________ is a smaller segment of DNA that carries the instructions for the synthesis of one polypeptide.
a. genome
b. intron
c. locus
d. gene
e. triplet
43. Genetic information for a polypeptide chain is written in the mRNA as ___________________.
a. codons
b. anticodons
c. triplets
d. four letter words
e. introns
44. Which of the following statements about RNA polymerase is TRUE?
a. RNA polymerase adds complementary RNA nucleotides during transcription
b. RNA polymerase is not involved in transcription
c. RNA polymerase is responsible for translation
d. RNA polymerase is used only in DNA replication
e. None of the above
45. Which of the following is g transcribed directly from DNA?
a. protein
b. exons
c. introns
d. mRNA
e. tRNA
46. Which of the following occurs when RNA polymerase attaches to the promoter in DNA?
a. elongation of the growing RNA molecule
b. termination of the RNA molecule
c. initiation of a new RNA molecule
d. initiation of a new polypeptide chain
e. none of the above
47. What are the non-coding segments of a stretch of eukaryotic DNA called?
a. introns
b. exons
c. codons
d. replicons
e. transposons
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Biology-1
Exam Three
48. Transcription
a. copies the base sequence in DNA to a complementary sequence of RNA
b. uses DNA as a template
c. is the synthesis of rRNA, mRNA and tRNA
d. takes place in the nucleus
e. is all of the above
49. In eukaryotes, transcription is terminated when
a. the ribosome reaches a stop codon in the mRNA
b. DNA polymerase transcribes a terminator sequence
c. RNA polymerase transcribes a terminator sequence
d. a cap and tail are added to mRNA
e. none of the above
50. The A-site on the ribosomal unit is the site where
a. mRNA binds
b. the tRNA molecule exits the ribosome
c. a tRNA with new amino acid binds
d. helicase unwinds the DNA helix
e. none of the above
51. The fact that GAA and GAG both code for glutamic acid demonstrates______________________ in the genetic
code.
a. redundancy
d. no ambiguity
b. reading frame
e. none of the above
c. triplet
52. Which of the following statements about ribosomes is false?
a. A ribosome consists of two subunits.
b. Ribosomal subunits are made of proteins and ribosomal RNA.
c. Each ribosome has two binding sites for tRNA molecules.
d. Ribosomes are not functional until both subunits are together
e. The ribosome is the where protein modification and packaging occur
53. A physical or chemical agent that changes the nucleotide sequence of DNA is called a(n)
a. terminator.
b. transposon.
c. mutagen.
d. anticodon.
54. If a tRNA had an CAU anticodon, it could attach to a(n) __________ mRNA codon.
a. UCG
b. AUG
c. TCG
d.UUG
e. GUA
55. Below are three statements. Which of the following choices properly matches the statements with the correct
biological processes?
I.
This occurs in the nucleus of eukaryotic cells.
II.
Transfer RNAs bind amino acids in the cytoplasm.
III.
A polymerase enzyme is required.
a. I: translation; II: translation; III: replication
b. I: transcription; II: translation; III: translation
c. I: transcription; II: translation; III: replication
d. I: replication; II: translation; III: transcription
e. I: replication; II: transcription; III: replication
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Biology-1
Exam Three
56.
What nucleotide sequence would be found on the partner DNA strand of the strand shown?
A) ACTGT
B) UGAGA
C) TGACA
D) TGUGU
57. Which plants in this figure must all be heterozygous?
A) purple-flowered plants in the P generation
B) white-flowered plants in the P generation
C) purple-flowered plants in the F1 generation
D) purple-flowered plants in the F2 generation
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