Biology 204Principles of Biology IAssignment 2AFor students with first

Biology 204Principles of Biology IAssignment 2AFor students with first

Biology 204Principles of Biology IAssignment 2AFor students with first names starting with the letters A to G.This assignment is graded out of 110 points, and is worth 10% of yourfinal mark. Please submit this assignment after you have completedChapter 16 and before you write the final exam. A. Definition/Comparison QuestionsInstructions: In your own words, define the pairs of terms given below.Write in complete sentences, stating the differences and relationshipsbetween the two terms, and give specific examples where appropriate. Acomplete answer usually requires four to eight sentences.Each question is worth four marks, for a total of 40 marks.1. histones / chromatin2. linkage / independent assortment3. autosomes / Y chromosome4. phosphodiester linkage / double helix5. adenine / thymine6. exons / pre-mRNA7. PCR / cloning8. Posttranscriptional regulation / translational regulation (re:eukaryotes)9. tRNA / rRNA10. lysogenic cycle / lytic cycle Principles of Biology I 1 B. Short Answer/Short Essay QuestionsInstructions: Answer each of the questions given below in your ownwords. Write in complete sentences where appropriate. A completeanswer usually requires one to two sentences per mark, so a three-markquestion would be answered in three to six sentences. This section isworth a total of 40 marks.(7 marks) 1. Describe the major phases of the cell cycle in a typical eukaryote. (2 marks) 2. Which major event during meiosis is most likely to producedeviations from Mendels laws? (6 marks) 3. Explain, with examples, the concept of jumping genes in prokaryotes. (5 marks) 4. Explain the variation of blood types in humans. (2 marks) 5. Compare prokaryotes and eukaryotes with regard to DNA that isNOT part of the nucleus/nucleoid. (4 marks) 6. Explain what it means that the genetic code is universal anddegenerate. (6 marks) 7. Using the following DNA template strand sequence, answer thequestions that follow:3?TACCAGCATGACTAA5?a. What is the complementary DNA sequence?b. What is the final sequence of amino acids in the peptideproduced?c. If the sequence is mutated so that an adenine is inserted beforeposition 11, how will the peptide be affected? What kind of amutation is this? (8 marks) 2 8. In fruit flies, grey colour is dominant over black colour and normalsized wings are dominant over vestigial wings. Suppose a truebreeding line of grey fruit flies with vestigial wings is mated with atrue breeding line of black fruit flies with normal wings. The F 1generation is then crossed. Draw a Punnett square to show thegenotypes of the F 2 generation, and give the phenotypic ratio for theF 2 generation. Biology 204 C. Multiple Choice QuestionsInstructions: Select the single best answer to each of the questions givenbelow. Each question is worth one mark, for a total of 30 marks.1. Breeding a yellow dog with a brown dog produced puppies withyellow and brown hairs intermixed. This is an example ofa. pleiotropy.b. codominance.c. incomplete dominance.d. epistasis.e. a polygenic trait.2. Chromosomes of eukaryotes consist ofa. DNA only.b. DNA and RNA.c. DNA and proteins.d. RNA only.e. proteins, DNA, and RNA.3. Tay-Sachs disease is a(n) ________ disease that results in blindness,mental retardation, and death due to ________.a. sex-linked; the absence of one of the sex chromosomesb. autosomal recessive; the accumulation of lipids in brain cellsc. X-linked; the accumulation of lipase in the cells of sweat glandsd. autosomal; the inability to break down amylase in the intestinese. autosomal dominant; accumulation of mucus in the lungs4. Genes that tend to be inherited together are said to bea. associated.b. related.c. similar.d. linked.e. alleles. Principles of Biology I 3 5. The mitotic spindle is made ofa. collagen.b. condensin.c. histones.d. keratin.e. microtubules.6. If meiosis did not occur in sexually reproducing organisms, thena. growth of the zygote would be halted.b. mitosis would be sufficient.c. gametes would remain haploid.d. chromosome number would double in each generation.e. eggs would be haploid, but sperm would be diploid.7. A Barr body in a mammalian female cell isa. an inactivated oocyte.b. a polar body.c. a degenerate nucleus.d. an inactivated X chromosome.e. an inactivated Y chromosome.8. After the S phase of mitosis, a replicated chromosome consists ofa. a chromosome tetrad. b. four sister chromatids.c. two sister chromatids.d. four homologous chromosomes.e. two homologous chromosomes.9. Which of the following cause the unwinding of the DNA doublehelix?a. DNA polymeraseb. DNA helicasec. RNA primerd. primosomee. RNA polymerase 4 Biology 204 10. Restriction enzymes have the following properties:a. they produce sticky ends on DNA fragments.b. they help DNA to replicate.c. they are involved in translation.d. they are found in most eukaryotes.e. all of the above.11. Which of the following diseases (left) does NOT match its descriptors(right)?a. sickle cell anemia: abnormal RBC; tissue damage due to a lack ofoxygen; autosomal recessive traitb. Tay-Sachs disease: blindness; membrane lipids accumulate inlysosomes; autosomal recessive traitc. Huntingtons disease: muscle spasms; develops late in life;autosomal recessive traitd. hemophilia A: internal bleeding; affects mostly males; X-linkedrecessive traite. cystic fibrosis: lung disease; defective membrane protein;autosomal recessive trait12. Most human somatic cells area. polyploid.b. diploid.c. aneuploid.d. tetraploid.e. haploid.13. The presence of detectable variation in the genomes of differentindividuals of a population is termeda. DNA sequencing.b. DNA electrophoresis.c. DNA tandem repeats.d. polymorphism.e. DNA profiling. Principles of Biology I 5 14. The lactose repressor blocks transcription of the lactose operon bya. turning off the appropriate genes in the intron. b. regulating the activity of the enzymes that the operon codes for.c. binding allosterically to the appropriate genes. d. slowing the uptake of lactose into the cell.e. binding to the operator. 15. In producing a genomic library, human DNA and plasmid DNA mustfirst be treated witha. the same restriction enzyme.b. different restriction enzymes.c. the same DNA ligase.d. different DNA ligases.e. none of the above.16. Autosomal aneuploidies arise bya. chromosome breakage and rejoining.b. nondisjunction.c. errors in crossing-over.d. mistakes in chromosome replication.e. single-gene mutations.17. The primer that is used during DNA replicationa. is called an Okazaki fragment.b. is used only once on the lagging strand.c. is a short RNA strand that is added to the 3 end.d. is used once on the leading strand.e. all of the above apply 18. The 3 end of a eukaryotic pre-mRNA is changed bya. removing the last phosphate group.b. adding a cap.c. copying the last few bases so that it can form a duplex structure.d. cutting and adding 100-250 adenine nucleotides.e. phosphorylation of the mRNA molecule. 6 Biology 204 19. Nucleosomesa. are groups of ribosomes.b. play a role in translation.c. are groups of chromosomes. d. are histones surrounded by DNA.e. contain RNA.20. An egg cell of a human was found to contain 22 chromosomes. Fromthis information, you can conclude thata. it is a normal egg cell.b. non-disjunction occurred during mitosis.c. non-disjunction occurred during meiosis.d. egg cells commonly have unusual chromosome numbers.e. the cell was diploid.21. ________ are alternative forms of a gene that govern the samefeature, such as flower colour, and occupy corresponding positionson homologous chromosomes.a. Allelesb. Locic. Homozygotesd. Coupled traitse. None of these22. Epistasis means thata. gene frequency will not change.b. there are no mutations.c. a particular gene has more than two alleles.d. a gene may influence the effect of another gene.e. linked genes have no effect on a particular phenotype. Principles of Biology I 7 23. Eukaryotic chromosomes consist ofa. circular DNA molecules complexed with positively-chargednonhistone proteins.b. circular DNA molecules complexed with negatively-chargedhistone proteins.c. linear DNA molecules complexed with positively-charged histoneproteins.d. linear DNA molecules comp
lexed with negatively-charged histoneproteins.e. circular DNA molecules.24. In the tryptophan operon, the repressor actively binds to the operatorwhena. tryptophan binds to an allosteric site on the repressor.b. tryptophan levels are low.c. lactose levels are low.d. there is a great need for proteins.e. allotryptophan levels are low.25. The probability of a couple having a child affected with an autosomalrecessive condition would bea. 0.5, or 50%, if both parents were homozygous normal.b. 0.5, or 50%, if both parents were heterozygous.c. 0.25, or 25%, if both parents were homozygous normal.d. 0.25, or 25%, if both parents were heterozygous.e. 0%, if both parents were heterozygous.26. A human female is homozygous for a particular allele. Which of thefollowing statements is NOT always true?a. She can pass the allele to her offspring.b. Her gametes have one copy of the allele.c. She has two copies of the allele in her somatic cells.d. She is true-breeding for that allele.e. Both of her parents must have been homozygous for the allele. 8 Biology 204 27. RNA interference inhibitsa. translation in general. b. translation of specific mRNAs.c. transcription of specific genes. d. DNA replication.e. the operator of a gene.28. Which of the following is FALSE about transposons?a. They are mobile DNA segments that can insert into geneticsequences and inactivate genes.b. They can spontaneously turn genes on and off.c. They are found only in bacteria.d. They can cause frameshift mutations in the genetic code.e. Some can replicate using reverse transcriptase.29. ________ is a technique that can be used to separate DNA moleculeson the basis of their size.a. Separation gradientb. Electrophoresisc. Selective sortingd. Cloninge. PCR30. Which of the following nucleotide sequences represents thecomplement to the DNA strand 5AGATCCG3?a. 5AGATCCG3b. 3AGATCCG5c. 5CTCGAAT3d. 3CTCGAAT5e. 3TCTAGGC5 End of Assignment 2A Principles of Biology I 9