Biol 1406: Exam IV
BIOLOGY 1406
GEN BIOLOGY I
Name _________________________________
Spring 2004
LOCKLIN
Exam IV
I. (25 points) Multiple choice. Select the correct answer for each question and place the answer on your exam in the blank to the left of the number.
_____1. Human eye color is the result of: a. Polygenic inheritance b. Codominance c. Simple dominance d. Sex-linked recessive inheritance e. Genes and environmental effects
_____2. Which of the following is (are) part of the structure of DNA? a. two sugar-phosphate "backbones" held together by hydrogen bonds between their bases b. the sugar ribose c. the four bases adenine, guanine, cytosine, and uracil. d. a long primary chain of amino acids e. none of the above
_____3. The three major kinds of mutational changes that can occur in DNA are a. point, insertion, and deletion c. transformation, translation, and transcription d. deletion, detraction, and reprogramming b. addition, subtraction, and multiplication e. all of the above are correct
_____4. Which of the following is (are) type(s) of selection which occur in nature? a. directional c. stabilizing b. disruptive d. all of the above
_____5. Semi-conservative DNA replication means: a. The old DNA is completely broken down c. A pairs with T and G pairs with C e. only a and b b. The old DNA remains completely intact d. Only half of the DNA is replicated e. Each new DNA molecule has half of the old one
_____6. The number of nucleotides in a sequence required to specify one amino acid is a. none c. 2 b. 1 d. 3 e. a variable number
_____7. A recessive allele on the X chromosome produces red-green color blindness in humans. A woman with normal vision but whose father was color blind marries a color-blind man. What percentage of their sons will be color blind? a. zero c. 50% e. 100% b. 25% d. 75%
_____8. The process in which DNA makes identical copies of itself is known as a. duplication b. multiplication c. substitution d. organization e. replication
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Biol 1406: Exam IV
_____9. Mutations: a. are random b. occur to solve problems for species (are goal oriented) c. are usually advantageous d. only choices a and b are correct e. are always detrimental
____10. The double helical structure of DNA was determined by a. Beadle and Tatum b. Watson and Crick c. Hershey and Chase d. Chase and Manhattan e. Watson and Holmes
____11. Assuming a Hardy-Weinberg equilibrium, 21% of a population is homozygous dominant, 50% is heterozygous, and 29% is homozygous recessive. What percentage of the next generation is predicted to be homozygous recessive? a. 21% b. 50% c. 29% d. 42% e. 58%
____12. DNA makes more copies of itself during the a. prophase b. S phase c. G
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phase d. metaphase e. G
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phase
____13. In the simplest (and somewhat inaccurate) definition, a gene is a. a long sequence of amino acids making the primary structure of a protein b. a short sequence of RNA nucleotides c. whatever we determine it to be d. several triplets that code for the same amino acid e. a long sequence of DNA nucleotides in a chromosome
____14. In the last century quite a few small towns were settled in the American West by pioneers. These towns have remained relatively isolated for the past 100 years or more and in many of them curious genetic characteristics have appeared. These towns are good examples of a. bottleneck effect b. founder effect c. temporal isolation d. cowboy mentality e. post-zygotic sterility
____15. A woman with normal vision but whose father was color-blind marries a color-blind man. What percentage of their female offspring may be color-blind? a. 0% b. 25% c. 50% d. 75% e. 100%
____16. The major difficulty in working out inheritance patterns in human beings is a. humans actually have no genetic material b. the adamant and vocal opposition of the fundamental religious right to all investigations of things sexual c. human genetics is very different from that of fruit flies and other organisms used in genetic research d. lack of large numbers of offspring from one mating e. none of the above is correct
____17. Why does the Hardy-Weinberg Equilibrium require that a population be very large? a. to eliminate effects of genetic drift b. to prevent mutation c. to eliminate effects of natural selection d. to prevent gene stoppage e. to ensure adequate sample size
____18. People who live in the “malaria belt” who are heterozygous for the sickle cell gene are also a. extremely anemic b. less fertile than normal c. malnourished d. resistant to malaria e. susceptible to hemophilia
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Biol 1406: Exam IV
____19. Which of the following is NOT a source of variation? a. mutation b. sexual reproduction c. meiosis d. crossing over e. natural selection
____20. A situation in which there are too many X-chromosomes in an individual resulting in the genetic make-up of
XXY is known as a. Turner's Syndrome b. Klinefelter's Syndrome c. Huntington's Syndrome d. Super Sex Syndrome e. none of the previous
____21. If only the largest or the smallest (not the intermediate phenotype) individuals are favored by natural selection in a particular habitat, what type of selection occurs? a. disruptive c. stabilizing b. directional d. dimorphic e. balanced
____22. In protein synthesis, each new amino acid is attached to the growing chain by a. an ionic bond b. RNA bond c. a physical bond d. peptide bond e. hydrogen bonds
____23. A particular gene has 489 bases that make it up. This gene may code for a polypeptide which is made up of
_____ amino acids. a. 1467 b. 978 c. 245 d. 163 e. 489
____24. Population bottlenecks are dangerous to a natural population because: a. problems due to inbreeding often result b. genetic variability is lost c. the potential for evolution is decreased d. a and b e. a, b, and c
____25. A male has a genetic disorder. Which one of these is inconsistent with X-linked recessive inheritance? a. both parents do not have the disorder b. only males in a pedigree chart have the disorder c. only females in previous generations have the disorder d. the sons of a female with the disorder will all have the disorder e. both a and c are inconsistent
II. (15 points) Fill in the blanks with the correct word or statement. The value of each question is in the parentheses following the number.
1. (1) Human blood types A, B, AB, and O, where one gene has several allele possibilities, is a good example of a kind of inheritance pattern known as ______________________________________ inheritance.
2. (2) In DNA, the sugar in each nucleotide is ____________________________ whereas in RNA it is
_______________________________.
3. (1) A species is defined as ______________________________________________________________ ____
_________________________________________________________________________________________.
4. (1) The process in which the message in DNA is made into mRNA is known as ________________________.
5. (1 ) A type of speciation in which 2 populations are geographically separated is ______________________.
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Biol 1406: Exam IV
6. (1) The major site(s) of protein synthesis inside a cell is(are) _____________________________________.
7. (1) When two homologous chromosomes fail to separate at Anaphase I of Meiosis I, this is known as a(n)
______________________________.
8. (1) Isolated populations founded by a small number of organisms is known as the ____________________________.
9. (1) Each tRNA has three RNA nucleotides, known as _______________________________(one word), which can bond to three mRNA nucleotides (codons).
10. (2) LIST two autosomal recessive human genetic diseases _________________________ and
_____________________________________.
11. (2) Commensalism is a type of ________________________ in which one species benefits and the other species is
_____________________________.
12. (1) LIST one of the ways RNA differs from DNA ______________________________________________
__________________________________________________________________________.
III. (12 points) Problem in human genetics.
The trait for red-green color blindness is a recessive, sex-linked trait. A color-blind woman marries a normal male and they want to know how many of their offspring they can expect to be color-blind. In the problem below use 'G' and 'g'.
(points per answer are in the parentheses before the answer)
(1) genotype of the mother _______________________(REMEMBER: sex-linked!!)
(1) genotype of the father ________________________(REMEMBER: sex-linked!!)
(2) type of gametes produced by the mother and ratio (or percentage) gamete type __________________ percentage of this type of gamete produced _____________ gamete type __________________ percentage of this type of gamete produced _____________
(2) gametes produced by the father and ratio (or percentage) gamete type __________________ percentage of this type of gamete produced _____________ gamete type __________________ percentage of this type of gamete produced _____________
(1) percent of children which be girls _______________________
(1) percent of children which be boys ________________________
(1) percent of children that will be color-blind _______________________________
(1) sex of the colorblind individual(s) ______________________________________
(1) percent of the children that will be carriers _______________________________
(1) sex of the children who are carriers _____________________________________
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Biol 1406: Exam IV
IV. (20 points) Matching. Place the letter of the correct answer from Column B into the blank to the left of the term in Column A. NOTE: There are more answers in Column B than you will need.
A B
____1. A, G, T, C a. all the genes (and their alleles) which occur in a population b. elaborate table tracing inheritance in humans c. a small RNA molecule with anticodons and a place for an amino acid to attach ____2. A, G, C, U
____3. autosomal traits d. a permanent change in the genetic material e. XYY f. XXY g. the nucleotide bases found in DNA ____4. population
____5. Allele frequency h. the process of making more DNA using the original double strand as a template to copy to make new strands i. the exotic Nile Perch which was introduced into Lake Victoria j. small strands of DNA beginning at the replication fork and eventually ____6. codon
____7. deletion
____8. Lates niloticus pieced together k. the change of DNA nucleotides into RNA nucleotides l. reductional division of the nucleus m. the external appearance of an organism
____9. gene pool n. all the organisms of different species in a given area o. the sequence of nucleotides in mRNA read three at a time
___10. Rhagoletis
___11. mutation
___12. Okazaki fragments
___13. Sexual Selection
___14. Jacob's Syndrome
___15. pedigree chart
___16. Biotic Factors
___17. replication
___18. bottleneck
___19. transcription
___20. tRNA p. parasitic fly of the Hawthorn trees q. population undergoes a drastic reduction in size due to a catastrophe r. the relative proportion of each allele of a gene in a population s. improper separation of chromosomes during meiosis t. the living component of the environment; competition, predator-prey interactions, etc. u. genes and alleles located on any chromosomes except the sex chromosomes v. a mutation resulting from the removal of a nucleotide w. all the organisms in the same species occurring in a given area x. nucleotide bases found in RNA y. strongest evidence that DNA is the genetic material; used radioactive Phosphorus and Sulfur and bacteriophages
z. explanation for bright coloration of male birds
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Biol 1406: Exam IV
V. (5 points) Short Answer.
Comment on the following situation: After a young wife gave birth to a third daughter, her husband's father approached her with an offer of one thousand dollars if she'd give birth next time to a son. Not only was this a ridiculous, disgusting, flagrant, and very rude insult, but also he was showing how ignorant he was of basic biology by approaching the wrong person. EXPLAIN.
VI. (10 points) SHORT Essay Hardy-Weinberg Equilibrium
ANSWER EITHER A or B not both!!!!!!!!!
The Hardy-Weinberg Equilibrium or Principle is considered to be the foundation for the 20th Century
Modern Synthetic Theory of Evolution.
A. (10 points) State the Hardy-Weinberg Equilibrium and then EXPLAIN what the Hardy-Weinberg
Equilibrium MEANS.
B (10 points) Discuss the conditions for Hardy-Weinberg Equilibrium and explain why any ONE of the five criteria cited in the Equilibrium probably does NOT hold (or take place) in nature.
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Biol 1406: Exam IV
Names: ______________________
______________________
______________________
______________________
VI. ESSAY (20 POINTS)
Below is a (very tiny) gene composed of DNA nucleotides. Using this gene, the Genetic Code Chart, and your knowledge of the whole process, describe ( this means written-out, complete sentences in your description ) how this gene is turned into a phenotype. (THERE IS MORE PAPER IF YOU NEED MORE.)
DNA: T A C C G G C T C A A A A G C G G G A G A G T C T T T C G T A A A A T T mRNA: tRNA: polypeptide:
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