DO NOT WRITE ON THIS EXAM. MARK ALL ANSWERS ON THE SCANTRON IN PENCIL.
Biology I: Modern Biology, Holt, Rinehart & Winston, © 2009
Unit3 Exam: Genetics & Biotechnology, Chapters 8-11
I. Multiple Choice: Darken the oval on the ScanTron with the corresponding correct answer.
1. During cell division, the DNA in eukaryotes is tightly coiled into compact structures called…
A. alleles B. chromosomes C. chromatin D. genes E. histones
2. Homologous chromosomes are 2 copies of …
A. autosomes B. sex chromosomes C. the same trait D. a karyotype E. haploid
3. Haploid cells include …
A. autosomes B. sperm cells
4. Prokaryotes duplicate using …
C. egg cells D. both B & C E. all the above
A. binary fission B. binary fusion
5. DNA is copied during …
C. growth plate D. fertilization E. both A & D
A. meiosis B. mitosis C. S phase of interphase D. oogenesis E. spermatogenesis
6. Cells grow to their mature size during this phase of interphase.
A. G
1
B. S C. G
2
D. Mitosis E. Meiosis
7. Karyotypes are made from chromosome at this phase of mitosis.
A. prophase B. metaphase C. anaphase D. telophase E. cytokinesis
8. Spindle fibers radiate from centrosomes during this phase of mitosis.
A. prophase B. metaphase C. anaphase D. telophase E. cytokinesis
9. DNA repair enzymes check the results of DNA replication at this checkpoint in the cell cycle.
A. G
1
B. S C. G
2
10. Synapsis formation occurs during …
A. four spermatids B. four diploid sperms
D. one gamete E. one zygote
D. Mitosis E. Meiosis
A. mitotic prophase B. Prophase I C. mitotic metaphase
11. Spermatogenesis results in the formation of …
D. Metaphase I
C. one spermatid + 3 polar bodies
E. Telophase I
12. Punnett Squares represent possible combinations of …
A. alleles B. chromosomes C. genes D. all the above
13. The source for genetic traits is …
A. DNA B. RNA C. protein D. amino acids
E. traits
E. all the above
14. DNA differs from RNA in that RNA has …
A. thymine B. uracil C. ribose D. both B & C E. both A & C

15. Pyrimidines include …
A. adenosine & thymine B. adenosine & guanine
D. cytosine & guanine E. cytosine & thymine
C. adenosine & cytosine
16. The person(s) who produced DNA’s X-ray crystallography to help elucidate DNA’s structure was…
A. Mrs. Watson B. Mrs. Crick C. Rosalind Franklin D. Maurice Wilkins E. both C & D
17. Gregor Mendel’s work with pea plants in the 1800’s relied on “true-breeding” plants. These were …
A. heterozygotes B. homozygotes C. monogamous D. fertile E. self-pollinating
18. Mendel noted that paired factors separate during formation of reproductive cells. This is known as..
A. Mendelian genetics B. law of segregation C. law of separation D. law of independent assortment
19. An organism’s appearance is its …
A. allele B. genotype C. phenotype D. dominant factor E. dihybrid cross
20. The resulting phenotypic ratio from crossing two heterozygotes is predicted to be …
A. 1 DD: 0 Dd: 0 dd B. 1 dominant: 0 recessive
D. 3 dominant: 1 recessive
C. 1 DD: 2 Dd: 1 dd
E. 1 dominant: 1 recessive
21. When you cross an unknown genotype with a homozygous recessive organism, you are doing a…
A. Punnett square B. dihybrid cross C. monohybrid cross D. testcross E. probability chart
22. When red four o’clocks flowers were crossed with white four o’clocks, pink flowers arose. This is ..
A. codominance B. complete dominance C. incomplete dominance D. mutations E. none of above
23. In heterozygous dihybrid cross, the expected phenotypic ratio, expressed as (homozygous dominant:
heterozygous dominant/ recessive: heterozygous recessive/ dominant; homozygous recessive) is…
A. 4: 3: 2: 1 B. 9:3:3:1 C. 3:2:2:1 D. 4:2:2:1 E. 4:4:4:4
24. Frederick Griffith’s experiments with virulent bacteria showed hereditary material could cause …
A. mutations B. death C. cancer D. pneumonia E. transformation
25. Using radioactively labeled bacteriophages, ___ demonstrated DNA was viral hereditary molecules.
A. Oswald Avery B. Frederick Griffith C. Martha Chase D. Alfred Hershey E. both C & D
26. The DNA double helix’s 2 strands are held together by ____ bonds.
A. covalent B. hydrogen C. ionic D. peptide E. nucleotide
27. A nucleotide consists of …
A. nucleic acids
D. pyrimidines
B. nucleosides
E. purines
C. 5-C sugar + phosphate + nitrogenous base
28. “ A C C T G T G A G A C” is an example of …
A. base-pairing rules B. complementary base pairs C. DNA base sequence
D. RNA base sequence E. genetic code
29. During DNA replication, these enzymes “unwind” DNA strands.
A. DNA polymerase B. RNA polymerase C. telomerase D. helicase E. replicase

30. During DNA replication, these enzymes add complementary nucleotides to original DNA strands.
A. DNA polymerase B. RNA polymerase C. telomerase D. helicase E. replicase
31. During transcription, these enzymes catalyze the formation of RNA on a DNA template.
A. DNA polymerase B. RNA polymerase C. telomerase D. helicase E. replicase
32. This is a product of transcription.
A. new DNA strand B. mRNA C. rRNA D. tRNA E. protein
33. This is a product of translation.
A. new DNA strand B. mRNA C. rRNA D. tRNA E. protein
34. This carries codon-matching amino acids to the ribosome.
A. new DNA strand B. mRNA C. rRNA D. tRNA E. protein
35. The 3-nucleotide mRNA sequence specifying a specific amino acid or start/stop signal is a …
A. anti-codon B. codon
36. An operon consists of …
C. purine D. pyrimidine E. promoter
A. structural genes B. operator C. promoter D. both A & B E. all the above
37. In the lac operon, the repressor protein is removed by binding of this factor.
A. anti-repressor protein B. lactose C. ligase
38. Introns are sections of RNA that serve as …
D. polymerase E. none of the above
A. regulators B. exons’ spacers C. genetic markers D. non-functional code E. vestigial code
39. Introns are not found in …
A. pre-mRNA B. RNA C. DNA D. both A & B E. both B & C
40. Transcription factors bind to RNA’s ___.
A. polymerase B. promoter C. enhancers D. activators E. both B & C
41. This regulates the placement of certain anatomical structures in organisms during morphogenesis.
A. structural genes B. operons C. homeotic genes D. euchromatin E. both A & B
42. Genes that can cause uncontrolled cell proliferation are known as…
A. homeobox genes B. proto-oncogene C. oncogenes D. carcinogens
43. The spread of cancer beyond its original site is known as…
E. maligogenes
A. tumorogenesis B. metastasis C. malignancy D. carcinoma E. lymphoma
44. The type of cancer that grows in bone and muscle tissue is known as …
A. carcinoma B. leukemia C. lymphoma D. metasoma E. sarcoma
45. Cancer developing in blood-forming tissues leading to uncontrolled white blood cell formation is…
A. carcinoma B. leukemia C. lymphoma D. metasoma E. sarcoma