101 Biology Test II- DeSaix
February 25, 2010
Name_____________________________
Print your name, last name first, and your PID number legibly on your answer sheet. Each answer is worth 2 points. Always choose one best answer and use only number 2 pencils to fill in your answers. Be sure to sign the pledge on your answer sheet. The last question will be used only if another question has to be deleted. Turn in your answer sheet in alphabetical order at the front of the room. Write down your answers on this copy to check against the key so that you will know what you have missed. The key will be posted on the blackboard website. _D__1. Which of the following terms refers to the situation where a single phenotypic characteristic is determined by the additive effects of genes at two or more loci? A. incomplete dominance, B. codominance, C. pleiotropy, D. polygenic inheritance, E. blending inheritance. _D__2. Genes located close together on the same chromosomes are referred to as ___ and generally ___. A. associated...sort independently during meiosis, B. linked...sort independently during meiosis, C. homologous...are inherited together, D. linked...do not sort independently during meiosis, E. codependent...do not sort independently during meiosis. _C__3. The work of Griffith indicated that: A. harmful strains of bacteria can mutate to become harmless B. bacteria mutate more frequently than most prokaryotes. C. harmless bacteria may be transformed in the presence of killed harmful bacteria. D. bacteria inject their nucleic acids into viruses causing transformation. E. bacteria can be labeled using P32. _C__4. Hershey and Chase worked with: A. virulent and non-virulent bacteria; B. Bacteria that infect viruses; C. virus protein coat and nucleic acid core; D. jumping genes; E. X-ray diffraction images of DNA. FREE_A__5. Which of the following could not be used in the production of different enzymes: A. a particular messenger RNA; B. a particular transfer RNA; C. a particular ribosomal RNA; D. a particular amino acid; E. a particular nucleotide. Because this did not say"eukaryotes" it is not a good question and everyone got credit for it. _D__6. What evidence shows that genes specify amino acid sequences in proteins? A. DNA is transcribed into a mRNA molecule. B. tRNA molecules have an amino acid attached to one end. C. Ribosomes contain RNA. D. A change in the base sequence of a gene changes the amino acid sequence of a protein. E. None of the above. _D__7. Protein Synthesis occurs: A. only in the nucleus, B. only in cells making enzymes, C. only in the digestive system, D. in the cytoplasm of most (probably all) cells, E. only in eukaryotes. _C__8. Homologous chromosomes separate from one another during ___ of meiosis: A) Prophase I B) Prophase II C) Anaphase I D) Anaphase II E) Telophase II. _A__9. Nondisjunction involving the sex chromosomes may occur during Meiosis I of spermatogenesis and produce two kinds of sperm. If these sperm fertilize normal eggs, which of the following pairs of genotypes are possible? A) XXY and XO B) XX and XY C) XYY and XO D) XYY and YO E) None of these. _A__10. Genes which have the same phenotypic effect in both the heterozygous and homozygous states are said to be: A) Dominant B) Phenotypic C) Recessive D) Assorting independently E) linked. __D_11. Which of the following processes adds new alleles to the gene pool? A) Crossing over between genes B) meiosis C) fertilization D) Mutations E) Selection. _D_12. Slight differences in monozygotic (identical) twins supports the hypothesis that: A) Dominance may be Incomplete B) Genetic traits are influence by many genes C) Single genes may produce multiple effects D) The environment affects the expression of genetic characteristics E) They developed from separate fertilized eggs. _B__13. Sickle cell anemia is: A) Observed only in heterozygotes B) Due to a single amino acid change in Hemoglobin C) The result of blood loss D) Due to a lack of oxygen. __C_14. A tall pea plant (TT) and a tall pea plant (Tt) have the same: A) Alleles B) Genotype C) Phenotype D) karyotype E) None of these.
2 _D__15. Visible traits (e.g. eye color) are controlled by genes: A) Only in response to environmental stimuli; B) Only as a result of mutation C) During gamete formation D) Through a series of enzymes. __C_16. The type of RNA which carries coded information from the nucleus to the ribosomes, but does not itself combine with amino acids is called: A) Ribosomal RNA B) Transfer RNA C) Messenger RNA D) Nucleolar RNA. _C__17. The anticondons of the tRNA molecules pair DIRECTLY with: A) Codons found in DNA B) Amino acids, moving them to the ribosomes C) mRNA codons D) RNA polymerase, so that mRNA may be transcribed from the DNA E) Ribosomal RNA in the larger subunit. _A__18. Protein synthesis is directed by the genetic code. Protein synthesis, in turn: A) Produces enzymes which determine development sequence B) Prevents malnutrition C) Directs the production of mRNA D) produces ATP _B__19. A genetic defect in humans results in the absence of sweat glands in the skin. Some men have this defect all over their bodies, but in women it is usually expressed in a peculiar way. A woman with the effect typically has small patches of skin with sweat glands and other patches where sweat glands are lacking. This pattern suggests the phenotypic effect of: A) A mutation B) Chromosome inactivation C) RNA splicing D) an operon E) The homeobox. _C__20. The rare trait ocular albinism (almost complete absence of eye pigment) is inherited as a sex-linked recessive. A man with ocular albinism marries a woman is a carrier. Which of the following is the best prediction concerning their offspring? A) All their sons will have ocular albinism, and all their daughters will be carriers; B) all their children of both sexes will have ocular albinism; C) About 50 percent of their sons and daughters will have ocular albinism D) About 50 percent of their daughters will have ocular albinism, but all their sons will have normal eyes; E) None of their children will have ocular albinism, but all their daughters will be carriers. _A__21. A man and a woman, both with freckles, had four children one of whom had no freckles. What assumption would you make of these circumstances? A) Freckles are caused by a dominant gene; B) The parents are homozygous dominant individuals for this trait; C) The appearance of the child without freckles is due to a mutation; D) Freckles is not a genetically based trait. For questions 22 28 determine whether the following statement refers to the completion of (A) mitosis, (B) meiosis, (C) both, or (D) neither. __A_22. production of haploid cells from haploid cells _B__23. produces genetically cells variable _A__24. allows multicellular organisms to grow _A__25. ensures that each body cell gets a complete set of genes __C_26. can produce haploid cells _B__27. produces haploid cells from diploid cells _C__28. occurs in the human body __C_ 29. Blood cells and muscle cells make different enzymes because: A) blood cells contain only genes for blood cell proteins and muscle cells contain only muscle protein genes B) all cells of an organism have all genes C) not every gene acts in every type of cell D) blood cells have hemoglobin while muscle cells have microtubules E) adult red blood cells lack nuclei in mammals. _A__ 30. In a Punnett square, the letters within the little boxes represent: A) offspring genotypes B) parental genotypes C) gametes D) offspring phenotypes E) parental phenotypes. _D__ 31. Which of the following statements about the eukaryotic chromosome is false? A) It is composed of DNA and protein. B) It is a linear structure. C) It replicates during interphase of mitosis. D) the number of genes on a particular chromosome vary from cell to cell. E) Active transcription occurs here. Deleted_B__ 32. Which point mutation would be most likely to have a catastrophic effect on the functioning of a protein? A) a base substitution. B) a base deletion near the start of a gene (but not in the start codon) C) a base deletion near the end of the coding sequence, (but not in the stop codon) D) deletion
of 3 bases near the start of the coding sequence (but not in the start codon) E) A base insertion near the end of the coding sequence, (but not in the stop codon). Because there was confusion about what a point mutation is, this question was not graded and question number 51 was used instead. _A__ 33. Genes at one locus that affect the expression of genes at a different locus are said to be: A) epistatic B) linked C) codominant D) penetrant E) alleles.
4 _A__ 34. A carrier of a genetic disorder who does not show symptoms is most likely to be: A) heterozygous for the trait and able to transmit it to offspring B) heterozygous for the trait but unable to transmit it to offspring C) heterozygous for the trait and able to transmit it to male offspring only D) homozygous for the trait and certain to transmit it to offspring E) homozygous for the trait and not certain to transmit it to offspring. __D_ 35. As proteins are being synthesized, tRNA molecules are constantly being released from the site of amino acid incorporation. What happens to these tRNA molecules? A) They return to the nucleus and bind to DNA again. B) They are used to code for synthesis of a protein. C) They immediately bind to another mRNA. D) They pick up another amino acid of the same type that they had before. E) They pick up an amino acid of another type, specifically the amino acid coded for by the codon next to the one to which they originally bound. _C__36. A dominant gene, R causes rust color in nods. Another independent dominant gene G produces grey nods. When the two dominant alleles occur together in the same individual, the fur is brown. Nods that are fully recessive at each of these two loci (rrgg) are white. When a brown female nod is mated to a grey male nod, the offspring occur in approximately the following ratio: 3/8 brown, 3/8 grey, 1/8 white and 1/8 rust. What are the genotypes of the two parents? A) RRGg and RrGg, B) RRGG and rrGG, C) RrGg and rrGg, D) RrGG and RrGG. _C__37. Which of the following genetic disorders can be detected by looking at an individual s chromosomes? A) sickle cell anemia B) phenylketonuria C) Down's syndrome D) hemophilia. __C_ 38.What is meant by "polar body twins" in humans? A) Two individuals that come from two polar bodies fertilized by the same sperm. B) Two individuals that come from one polar body and one egg fertilized by the same sperm. C) Two individuals that come from one polar body and one egg fertilized by different sperm. D) Twins that are formed from cells that split into two with one set of cells going toward one pole of the developing embryo and the other at the opposite end. E) Twins born during polar expeditions. __D_ 39. Which of the following crosses would serve as a testcross for BOTH characteristics A and B? A) AaBb x AaBb B) AaBb x aaBB C) AABB x Aabb D) AaBb x aabb E. AABB x Aabb. _E__ 40. Which of the following does not involve complimentary base pairing? A) DNA replication B) tRNA/mRNA match up C) transcription D) translation E) nucleotide assembly (making nucleotides). _A__41. A biologist examined mitotically dividing cells and found that the amount of DNA per cell in prophase was equal to x. What would be the DNA per cell in anaphase? A) x B) 2x C) x/2 D) x/4 E) 4x. __C_42. What does meiosis do? A) fuses an egg cell with a sperm cell B) allows a haploid cells to yield diploid cells C) allows diploid cells to yield haploid cells D) reproduces a diploid set of chromosomes E) none of the above. __E_43. The basic structure of chromatin has sometimes been referred to as beads on a string of DNA. These beads are called: a) chromosomes. B) chromatids. C) supercoils. D) interphases. E) nucleosomes. __D_44. In plant cells, cytokinesis is accomplished by the formation of a(n): a) aster. B) membrane furrow. C) equatorial plate. D) cell plate. E) spindle. __B_45. Zygotes are: a) multicellular. B) diploid. C) animals. D) clones. E) gametes. __C_46. Nucleic acids are made of (choose the best answer): A) Amino acids B) Adenine and uracil C) Nucleotides D) Phosphate groups E) Proteins __B_47. During meiosis I in humans, one of the daughter cells receives: a) only maternal chromosomes. B) a mixture of maternal and paternal chromosomes. C) the same number of chromosomes as a diploid cell. d) a sister chromatid from each chromosome. E) one-fourth the amount of DNA in the parent nucleus. __C_48. A deoxyribose nucleotide is a: a) deoxyribose plus a nitrogenous base. B) sugar and a phosphate. C) deoxyribose plus a nitrogenous base and a phosphate. D) ribose plus a nitrogenous base. E) nitrogenous base bonded to an amino acid backbone backbone. _D__49. A man and woman are both of normal pigmentation, but both have one parent who is albino (without melanin pigmentation). Albinism is an autosomal (not sex-linked) recessive trait. What is the
probability that their first child will be an albino? A) 100%
0%
B) 1/8
C)
D)
E)
_B__50. How many unique gametes could be produced through by an individual with the genotype AABbCCDd? A) 32 B) 4 C) 16 D) 8 E) 1/64. _B__51. An allele is: A) A chromosome pair. B) one of two or more genes for a particular character located at the same place on homologous chromosome. C) the genetic make-up of an organism. D) the point of attachment of spindle fibers.