UTSC BIOA01 Life on Earth term test module two |50 expected exam questions and correct answers (in bold) |NEW UPDATE

UTSC BIOA01 Life on Earth term test module two |50 expected exam questions and correct answers (in bold) |NEW UPDATE UTSC BIOA01 F Life on Earth term test module two 50 expected exam questions and correct answers (in bold) NEW UPDATE chapter nine 1. during the cell cycle, the dna mass of a cell a. decreases during g1 phase b. decreases during metaphase c. increases during the s phase d. increases during g2 phase e. decreases during interphase 2. honeybee eggs that are not fertilized develop into fertile haploid males called 'drones'. fertilized eggs can develop into diploid females, one of which might because a 'queen'. (fertilized eggs might also become males, but they are taken out and killed by the drones) if the queen has 32 chromosomes in her body cells, how many chromatids would be present in a g2 drone cell? a. 8 b. 16 c. 24 d. 32 e. 64 3. the major microtubule organizing centre of the animal cell is a. chromosomes, composed of chromatids b. the centrosome, composed of centrioles c. the chromatin, composed of chromatids d. chromosomes, composed of centromere e. centrioles, composed of centrosome 4. for a given cell, the number of is higher at the end of s phase than at the beginning. a. nuclei b. chromatids c. chromosomes d. CDK2 molecules e. both b and c are correct 5. which of the following statements about mitosis is incorrect? a. microtubules can bind to kinetochores and interact with other microtubules from opposite poles b. in anaphase, the spindle separates sister chromatids and pulls them apart c. chromosomes congregate near the centre of the cell during metaphase. d. cytokinesis describes the movement of chromosomes e. both the animal cell furrow and the plant cell plate form at their former spindle midpoints 6. in bacteria. a. several chromosomes undergo mitosis b. binary fission produces four daughter cells c. replication begins at the ori and the dna strand separates d. replication occurs in the same direction off each opposite strand e. the daughter cells receive different genetic information from the parent cell. chapter ten 7. if recombination occurred between bacteria as shown in the figure, the result would be (page 226 Q#1) a. Mhv and mhV b. MHV and mhv c. Mhv and mHv d. MHV and mhV e. mhv and MhV 8. which of the following is not correct for bacterial conjugation? a. both Hfr and F+ bacteria have the ability to code for a sex pilus b. after an f- cell has conjugated with an f+, its plasmid holds the f+ factor c. the recipient cell usually becomes Hfr following conjugation d. in an Hfr x F- mating, dna of the main chromosome moves to a recipient cell. e. genes on the f factor encode proteins of the sex pilus. 9. which of the following is not correct for bacterial transformation? a. artifical tranformation is used in cloning procedures. b. avery was able to tranform live noninfective bacteria with dna from dead infective bacteria c. the cell wall and plasma membrane must be penetrated for tranformation to proceed d. a virus is required for the process e. electroporation is a form of artificial tranformation used to introduce dna into cells 10. transduction a. may allow recombination of newly introduced dna with host cell dna b. is the movement of dna from one bacterial cell to another by means of a plasmid c. can cause the dna of the donor to change but not the dna of the recipient d. is the movement of viral dna but not bacterial dna into a recipient bacterium e. requires physical contact between the two bacterium 11. the diploid number of this individual is 6 (see page 227 Q#6) (three maternal chromosomes and their paternal homologues lined up in the middle) this figure represents: a. mitotic metaphase b. meiotic metaphase I c. meiotic metaphase II d. a gamete e. six nonhomolgous chromosomes 12. chiasmata a. form during metaphase II of meiosis b. occur between two nonhomologous chromosomes. c. represent chromosomes independently assorting d. are sites of dna exchange between homologous chromatids e. ensure that the resulting cells are identical to the parent cell 13. if 2n is four, the number of possible combinations in the resulting gametes is a. 1 b. 2 c. 4 d. 8 e. 16 14. the number of human chromosomes in a cell in prophase I of meiosis is and in telophase II is . a. 92; 46 b. 46; 23 c. 23; 23 d. 23; 16 e. 4; 2 15. the dna content in a diploid cell in g2 is x. if that cell goes into meiosis at its metaphase II, the dna content would be a. 0.1x b. 0.5x c. x d. 2x e. 4x chapter eleven 16. the dominant C allele of a gene that controls color in corn produces kernels with colors; plants homozygous for a recessive c allele of this gene have colorless or white kernels. what kinds of gametes, and in what proportions, would be produced by the plants in the following crosses? what seed color and in what proportions would be expected in the offspring of the crosses? a. CC x Cc b. Cc x Cc c. Cc x cc 17. in peas, the allele T produces tall plants and the allele t produces dwarf plants. the T allele is dominant to t. if a tall plant is crossed with a dwarf, the offspring are distributed about equally between tall and dwarf plants. what are the genotypes of the parents? 18. the ability of humans to taste the bitter chemical phenylthiocarbamide (PTC) is a genetic trait. people with at least one copy of the normal, dominant allele of the PTC gene can taste PTC; those who are homozygous for a mutant, recessive allele cannot taste it. could two parents able to taste PTC have a nontaster child? could nontaster paretns have a child able to taste PTC? a pair of taster parents, both of whom had one parent able to taste PTC and one nontaster parent, are expecting their first child. what is the chance that the child will be able to taste PTC? unable to taste PTC? suppose the first child is a nontaster. what is the chance that their second child will also be unable to taste PTC? 19. one gene has the alleles A and a; another gene has the alleles B and b. for each of the following genotypes, what types of gametes will be produced, and in what proportions, if the two gene pairs assort independently? a. AA BB b. Aa BB c. Aa bb d. Aa Bb 20. what genotypes, and in what frequencies, will be present in the offspring from the following matings? a. AA BB x aa BB b. Aa BB x AA Bb c. Aa Bb x aa bb d. Aa Bb x Aa Bb 21. in addition to the two genes in problem 14, assume you now study a third independently assorting gene that has the alleles C and c. for each of the following genotypes, indicate what types of gametes will be produced a. AA BB CC b. Aa BB cc c. Aa BB Cc d. Aa Bb Cc 22. a man is homozygous dominant for alleles at 10 different genes that assort independently. how many genotypically different types of sperm cells can he produce? a woman is homozygous recessive for the alleles of 8 of these 10 genes, but she is heterozygous for the other two genes. how many genotypically different types of eggs can she produce? what hypothesis can you suggest to describe the relationship between the number of different possible gametes and the number of heterozygous and homozygous genes that are present? 23. in guinea pigs, an allele for rough fur, R, is dominant over an allele for smooth fur, r; an allele for black coat, B, is dominant over that for white, b. you have an animal with rough, black fur. what cross would you use to determine whether the animal is homozygous for these traits? what phenotype would you expect in the offspring if the animal is homozygous? 24. in garden peas, the genotypes GG or Gg produce green pods and gg produces yellow pods; TT or Tt plants are tall and tt plants are dwarfed; RR or Rr produce round seeds and rr produces wrinkled seeds. if a plant of a true- breeding, tall variety with green pods and round seeds is crossed with a plant of a true-breeding, dwarf variety with yellow pods and wrinkled seeds, what phenotypes are expected, and in what ratios, in the f1 generation? what phenotypes, and in what ratios, are expected if f1 individuals are crossed? 25. in chickens, feathered legs are produced by a dominant allele F. another allele f of the same gene produces ffeatherless legs, the dominant allele P of a gene at a different locus produces pea combs; a rececessive allele p of this gene causes single combs. a breeder makes the following crosses with birds 1,2,3 and 4; all parrents have feathered legs and pea combs: cross offspring 1x2 all feathered, pea comb 1x3 ¾ feathered; ¼ featherless, all pea comb 1x4 9/16 feathered, pea comb; 3/16 featherless, pea comb; 3/16 feathered, single comb; 1/16 featherless, single comb what are the genotypes of the four birds? chapter thirteen 26. working on the amazon river, a biologist isolated dna from two unknown organisms, P and Q. he discovered that the adenine content of P was 15% and the cytosine content of Q was 42%, this means that a. the amount of guanine in P is 15% b. the amount of guanine and cytosine combined in P is 70% c. the amount of adenine in Q is 42% d. the amount of thymine in Q is 21% e. it takes more energy to unwind the dna of P than the dna of Q 27. the hershey and chase experiment showed that viral a. 35S entered bacterial cells b. 32P remained outside of bacterial cells c. protein entered bacterial cells d. dna entered bacterial cells e, dna mutated in bacterial cells 28. pyrimidines include a. cytosine and thymine b. adenine, cytosine, and guanine. c. adenine and thumine. d. cytosine and guanine. e. adenine and guanine. 29. which of the following statements about dna replication is false? a. synthesis of the new dna strand is from 3' to 5' b. synthesis of the new dna strand is from 5' to 3' c. dna unwinds, primase adds rna primer, and dna polymerases synthesize the new strand and remove the rna primer d. many initiation points exist in each eukaryotic chromosome. e. okazaki fragments are synthesized in the opposite direction from the direction in which the replication fork moves 30. which of the following statements about dna is false? a. phosphate is linked to the 5' and 3' carbons of adjacent deoxyribose molecules b. dna is bdirectional in its synthesis c. each side of the helix is antiparallel to the other. d. the binding of adenine to thymine is through three hydrogen bonds. e. avery identified dna as the transforming factor in crosses between smooth and rough bacteria 31. during replication, dna is synthesized in a 5' to 3' direction. this implies that a. the template is read in a 5' to 3' direction b. successive nucleotides are added to the 3'-OH end of the newly forming chain c. because both strands are replicated nearly simultaneously, replication must be continuous on both. d. ligase unwinds dna in a 5' to 3' direction e. primase acts on the 3' end of the replicating strand 32. telomerase a. is active in cancer cells b. is more active in adult than in embryonic cells c. complexes with the ribosome to form telomeres. d. acts on unique genes called telomeres e, shortens the ends of chromosomes 33. mismatch repair is the ability a. to seal okazaki fragments with ligase into a continual dna strand b. of primase to remove the rna primer and replace it with the correct dna c. of some enzymes to sense the insertion of an incorrect nucleotide, remove it, and use a dna polymerase to insert the correct one d. to correct mispaired chromosomes in prophase I of meiosis e. to remove worn-out dna by telomerase and replace it with newly synthesized nucleotides 34. prokaryotic dna a. is surrounded by densely packed histones b. has many sites for the initiation of dna replication c. has both strands synthesized in the same direction d. is packaged as euchromatin and heterochromatin e. is packaged as a large circular chromosome. chapter fourteen 35. eukaryotic mrna a. uses snrnps to cut out introns and seal together translatable exons b. uses a spliceosome mechanism made of dna to recognize consensus regions to cut and splice c. has a guanine cap on its 3' end and a poly(A) tail on its 5' end d. is composed of adenine, thymine, guanine, and cytosine. e. codes the guanine cap and poly(A) tail from the dna templates 36. a segment strand of dna has a base sequence of 5'-GCATTAGAC-3' what would be the sequence of an RNA molecule complementary to that sequence? a. 5'-GUCTAATGC-3' b. 5'-GCAUUAGAC-3' c. 5'-CGTAATCTG-3' d. 5'-GUCUAAUGC-3' e. 5'-CGUAAUCUG-3' 37. which of the following ttypes of bonding does not invove complementary base pairing? a. codon to anticodon b. signal peptide to signal recognition particle c. rna to rna in hairpin transcription terminator d. dna to rna in transcription of snrna gene e. rrna to mrna in prokaryotic translation initiation 38. translation is in progress,with methionine bound to a trna in the P site, and a phenylalanine bound to a trna in the A site. the order of the next steps in the elongation cycle is a. the ribosome translocates -> a new aminoacyl-trna enters the A site -> peptidyl transferase catalyses a peptide bond between the two amino acids -> empty trna is reeased from the ribosome. b. peptidyl tranferase catalyzes a peptide bond between the two amino acids -> a new aminoacyl-trna enters the A site -> empty trna is released from the ribosome -> the ribosome translocates c. peptidyl transferase catalyzes a peptide bond between the two amino acids -> empty trna is released from the ribosome -> a new aminoacyl-trna enters the A site – the ribosome translocates d. peptidyl transferase catalyzes a peptide bond between the two amino acids -> the ribosome translocates -> empty trna is released from the ribosome -> a new aminoacyl-trna enters the A site e. the ribosome translocates -> peptidyl transferase catalyzes a peptide bond between the two amino acids -> empty trna is released from the ribosome -> a new aminoacyl-trna enters the A site 39. which of the following statements is false? a. gtp is an energy source during various stages of translation b. in the ribosome, peptidyl transferase catalyses peptide bond formation between amino acids c. when the mrna code uaa reaches the ribosome there is no trna to bind to it d. a long polypepptide is cut off the trna in the a site so its met amino acid links to the animoacid in the P site. e. fourty-two amino acids of a protein are encoded by 126 nucleotides of the mrna, 40. which item binds to srp receptor and to the signal sequence to guide a newly synthesized protein to be secreted to its proper 'channel'? a. ribosome b. signal recognition particle c. endoplasmic reticulum d. signal peptidase e. receptor protein 41. a part of an mrna molecule with the sequence 5'-UGC GCA-3' is being translated by a ribosome. the following activated trna molecules are available. two of them can correctly bind the mrna so that a dipeptide can form. trna anticodon amino acid 3'-GGC-5' proline 3'-CGU-5' analine 3'-UGC-5' threonine 3'-CCG-5' glycine 3'-ACG-5' cysteine 3'-CGG-5' alanine a. cysteine-alanine b. proline-cysteine c. glycine-cysteine d. alanine-alanine e. threonine-glycine chapter fifteeen 42. the control of the delivery of mrna to the cytoplasm is an example of a. translational regulation b. posttranslational regulation c. transcriptional regulation d. postranscriptional regulation e. deoxyribonucleic regulation 43. chromatin remodeling activates gene expression when it a. allows proteins initiating transcription to disengage from the promoter b. winds genes tightly around histones. c. deacetylates histones d. inserts nucleosomes into chromatin e. recruits a protein complex that displaces nucleosome from the promoter chapter sixteen 44. using cdna is associated with which of the following? a. introns can be identified and sequenced by this method b. it measures both active and inactive dna c. promoter regions can be identified by this method d. one can identify start and stop regions by this method e. one can identify active mrna and make a complementary dna sequence to the mrna 45. restriction endonucleases, ligases, plasmids, viral or yeast vectors, electrophoresis gels, and a bacteria gene resistant to an antibiotic are al required for: a. dideoxyribonucleotide analysis b. pcr. c. dna cloning d. dna fingerprinting e. dna sequencing 46. the pcr technique is distinguished from other processes discussed in this chapter by the use of a. primers b. dna c. rna d. taq polymerase e. the four nucleoside triphoshates 47. dna fingerprinting a. compares one stretch of the same dna between two or more people b. measures different lengths of dna from many repeating noncoding regions for comparison between two or more people c. requires the larrgest dna lengths to run the greatest distance on a gel d. requires amplification after the gels are run e. can easiydifferentiate dna between identical twins 48. the sequence of the human genome a. was obtained by sequencing overlapping dna fragments b. revealed far more genes than expected c. revealed 3 trillion base pairs d. used techniques not applicabe to mapping other species e. revealed 250 000 protein-coding genes 49. sanger's dna sequencing technique a. uses dideoxyribonucleotides to make new full-length strands of dna b. is based on cellular respiration c. requires an rna template, an rna primer, rna polymerase, reverse transcriptase, and the dideoxyribonucleotides, ddatp, ddutp, ddctp, and ddgtp. d. places the rna template to be sequenced on a gel and then adds the other igredients from c. e. is based on dna replication 50. a microarray could beused to a. sequence dna form several chromosomes in one individual b. synthesize multiple copies of dna from several sources c. propagate human germ-line cells for cloning d. compare coding dna from a patient's normal lung cells with coding dna from his cancerous lung cells e. determine proteins that are expressed under certain environmental conditions