58 terms

Biology Test 2

1. During metaphase ______.
Chromosomes line up on the midline of the cell.
Amanda's abnormal number of sex chromosomes resulted from ____________.
Nondisjunction in meiosis
4. Sexual intercourse in humans ______.
fertilization of two haploid cells
5. Cytokinesis occurs during the ______ stage of mitosis.
During telophase
the reverse of .... happens. goes from 92 chromosomes to 2 daughter cells with 46
9. The mitotic cell cycle results in the production of ______.
Two identical daugher cells with full complements of DNA
10. Crossing over during prophase I results in ______.
chromosomes of a homologous pair breaks and exchange genes. /Rearrangement of genetic material
11. Sister chromatids are joined at the ______.
12. Nucleosomes are made of ______.
DNA wound around histosomes
13. Hoe is Genetic variation is accomplished
18. Which of the following is the best description of the events of anaphase I?
Homologous chromosomes randomly separate and migrate to opposite poles.
This pedigree supports the fact that widow's peak is due to a dominant allele, because if it were due to a recessive allele and both parents show the recessive phenotype, then ______.
All of the offspring would have widows peak.
21. What name is given to the specific location of a gene on a chromosome?
Locus, Loci
23. According to Mendel's principle of segregation, ______.
A sperm/egg cell only carriers one allele for each inherited characteristic... P146
25. What if children with this disease always have attached earlobes, a recessive trait and a trait that is independently inherited. If both parents are heterozygous for attached earlobes, what is the probability that the second child will have the disease?
¼ 1/16
27. Marfan syndrome is the result of inheriting a single allele. Individuals with Marfan syndrome are tall and long-limbed, and have both cardiovascular and eye defects. The inheritance of Marfan syndrome is an example of ______.
28. Which of these crosses will only produce heterozygous offspring?
aa × aa
29. An individual with the blood group genotype LMLN has the phenotype MN. What is the relationship between the LM and LN alleles?
32. Hypophosphatemia (vitamin D-resistant rickets) is inherited as an X-linked dominant. What is the expected outcome of a cross between a homozygous recessive woman and a man with hypophosphatemia?
All offspring exhibit hypophosphatmia.
33. To determine the phenotype of an individual who expresses a dominant trait, you would cross that individual with an individual who ______.
Is homozygous recessive for the trait.
34. Attached earlobes are recessive to free earlobes. What genotypic ratio is expected when an individual with attached earlobes mates with an individual heterozygous for free earlobes?
37. Attached earlobes are recessive to free earlobes. What is the probability of having a child with attached earlobes when an individual with attached earlobes mates with an individual heterozygous for free earlobes?
39. What type of chemical bond joins the bases of complementary DNA strands?
40. How can bacteriophage DNA be spread from cell to cell without causing cell death?
Vialysogenic cycle
41. Once viruses are detected, the number of viruses increases rapidly. This is because ______.
the viruses lyse the hosts to release mature viruses all at once
42. The expressed (coding) regions of eukaryotic genes are called ______.
45. Which of the following enzymes is responsible for RNA synthesis?
RNA Polymerase
48. The correct sequence of events occurring during transcription is ______.
initiation, elongation, termination
49. What name is given to the collection of traits exhibited by an organism?
50. DNA and RNA are polymers composed of ______ monomers.
51. After replication, ______. (what is the composition of the new strands?)
one stand is old and one is new
52. HIV (human immunodeficiency virus) must use its own ______ to reproduce. (its unique enzyme is called what?)
reverse transcriptase
53. The RNA that is translated into a polypeptide is ______ RNA.
54. The modern phrasing of Beadle and Tatum's hypothesis about relationships between genes and their products is "one gene-one ______."
55. Transcription factors attach to ______.
56. The process by which genotype becomes expressed as phenotype is ______.
59. A gene operon consists of ______.
transcribed genes, a promoter, and a regulatory gene.
61. The ______ acts as an on/off switch. (0f the operon)
63. What would you assume if you found RNA transcripts of lactose-utilizing genes within E. coli?
The presence of lactose
64. Developmental similarities among very different animals can be attributed to ______.
shared homeoboxes
65. Cutting DNA with a particular restriction enzyme produces ______ that can be separated by gel electrophoresis.
restriction fragments
67. An advantage of using reverse transcriptaanse to prepare a gene for cloning is that ______.
the resulting DNA strand does not code for a protein
68. The process of making multiple copies of a gene by inserting it into a host genome and culturing the host is called ______.
gene cloning
69. The following figure provides you with an overview of recombinant technology. The end result is a transgenic bacterium with a human gene that codes for marketable quantities of a human gene product. However, molecular biologists frequently have problems with the product. One problem might be ______.
production of a human protein that is unable to function properly
70. A DNA fragment with a sticky end that reads -ATTCG will bind with another DNA fragment with a sticky end that reads ______.
TAAGC- G - C A - T
73. The following figure shows that gel electrophoresis can be used to separate repetitive DNA sequences. Gel electrophoresis separates DNA fragments because ______.
DNA fragments have a negative charge and move to the positive pole
74. Nucleic acid probes are used to ______.
Identify a specific nucleotide sequence
75. DNA fragments that have matching sticky ends are joined by bonds formed by the action of ______. (name the enzyme)
DNA ligase
76. Homologous chromosomes carry the same what? ______.
77. Both mitosis and meiosis are preceded by ______.
78. The genetic material is duplicated during ______ of the cell cycle.
the S phase
80. What protects mRNA from attack by cytoplasmic enzymes?
a cap and tail
81. Translation converts the information stored in ______ to ______.
RNA, Polypeptide
82. Transcription is the ______.
manufacture of a strand of RNA complementary to a strand of DNA
83. If one strand of a DNA double helix has the sequence GTCCAT, what is the sequence of the other strand?
85. Bacterial RNA polymerase binds to the ______.
87. A ______ is a chromosomal landmark whose inheritance can be tracked.
Genetic marker
which of these can act as a vector to introduce new genes into a cell?