CHAPTER 5DNA AND CHROMOSOMESThe Structure and Function of DNAThe Structure of Eucaryotic ChromosomesThe Regulation of Chromosome StructureCHAPTER 5DNA AND CHROMOSOMES 2009 Garland Science PublishingThe Structure and Function of DNA5-1 Using terms from the list below, fill in the blanks in the following brief description of the experiment with Streptococcus pneumoniae that identified which biological molecule carries heritable genetic information. Some terms may be used more than once.Cell-free extracts from S-strain cells of S. pneumoniae were fractionated to __________________ DNA, RNA, protein, and other cell components. Each fraction was then mixed with __________________ cells of S. pneumoniae. Its ability to change these into cells with __________________ properties resembling the __________________ cells was tested by injecting the mixture into mice. Only the fraction containing __________________ was able to __________________ the __________________ cells to __________________ (or __________________ ) cells that could kill mice.carbohydrate lipid R-strainDNA nonpathogenic RNAidentify pathogenic S-strainlabel purify transform5-2 Many of the breakthroughs in modern biology came after Watson and Crick published their model of DNA in 1953. In what decade did scientists first identify chromosomes?(a) 1880s(b) 1920s(c) 1940s(d) 1780s5-3 Mitotic chromosomes were first visualized in the 1880s with the use of very simple tools:a basic light microscope and some dyes. Which of the following characteristics of mitoticchromosomes reflects how they were named?(a) motion(b) color(c) shape(d) location5-4 In a DNA double helix, _____________________.(a) the two DNA strands are identical(b) purines pair with purines(c) thymine pairs with cytosine(d) the two DNA strands run antiparallel5-5 Indicate whether the following statements are true or false. If a statement is false, explain why it is false.A. DNA molecules, like proteins, consist of a single, long polymeric chain that is assembled from small monomeric subunits.B. The polarity of a DNA strand results from the polarity of the nucleotide subunits.C. There are five different nucleotides that become incorporated into a DNA strand.D. Hydrogen bonds between each nucleotide hold individual DNA strands together.5-6 Several experiments were required to demonstrate how traits are inherited. Which scientist or team of scientists first demonstrated that cells contain some component that can be transferred to a new population of cells and permanently cause changes in the newcells?(a) Griffith(b) Watson and Crick(c) Avery, MacLeod, and McCarty(d) Hershey and Chase5-7 Several experiments were required to demonstrate how traits are inherited. Which scientist or team of scientists obtained definitive results demonstrating that DNA is the genetic molecule?(a) Griffith(b) Watson(c) Crick(d) Hershey and Chase5-8 Which of the following chemical groups is not used to construct a DNA molecule?(a) five-carbon sugar(b) phosphate(c) nitrogen-containing base(d) six-carbon sugar5-9 Which of the following sequences can fully base-pair with itself?(a) 5′-AAGCCGAA-3′(b) 5′-AAGCCGTT-3′(c) 5′-AAGCGCAA-3′(d) 5′-AAGCGCTT-3′5-10 The DNA from two different species can often be distinguished by a difference in the ______________________.(a) ratio of A + T to G + C(b) ratio of A + G to C + T(c) ratio of sugar to phosphate(d) presence of bases other than A, G, C, and T5-11 For a better understanding of DNA structure, it helps to be able to compare physical characteristics evident from a side view of double-stranded DNA with those of individualbase pairs.A. Use brackets to designate the major and minor grooves on Figure Q5-11A and shade in the surface that will be exposed in the major grove in Figure Q5-11B.B. If base pairs were aligned and stacked directly on top of each other, the major and minor grooves would be linear depressions all along the DNA. Explain why this isnot the actual conformation of a DNA molecule.Figure Q5-115-12 Which DNA base pair is represented in Figure Q5-12?(a) A-T(b) T-A(c) G-C(d) C-GFigure Q5-125-13 Use the terms listed to fill in the blanks in Figure Q5-13.A. A-T base pairB. G-C base pairC. deoxyriboseD. phosphodiester bondsE. purine baseF. pyrimidine baseFigure Q5-135-14 The structures of the four bases in DNA are given in Figure Q5-14.Figure Q5-14A. Which are purines and which are pyrimidines?B. Which bases pair with each other in double-stranded DNA?5-15 Using the structures in Figure Q5-15 as a guide, sketch the hydrogen bonds between the base pairs in DNA. Hint: The bases in the figure are all drawn with the –NH– that attaches to the sugar at the bottom of the structure.5-16 Because hydrogen bonds hold the two strands of a DNA molecule together, the strands can be separated without breaking any covalent bonds. Every unique DNAmolecule “melts” at a different temperature. In this context, Tm, melting temperature, is the point at which two strands separate, or become denatured. Order the DNA sequences listed below according to relative melting temperatures(from lowest Tm to highest Tm). Assume that they all begin as stable double-stranded DNA molecules. Explain your answer.A. GGCGCACCB. TATTGTCTC. GACTCCTGD. CTAACTGG5-17 Indicate whether the following statements are true or false. If a statement is false, explain why it is false.A. Each strand of DNA contains all the information needed to create a new double-stranded DNA molecule with the same sequence information.B. All functional DNA sequences inside a cell code for protein products.C. Gene expression is the process of duplicating genes during DNA replication.D. Gene sequences correspond exactly to the respective protein sequences produced from them.5-18 The complete set of information found in a given organism’s DNA is called its ____________.(a) genetic code(b) coding sequence(c) gene(d) genome5-19 The manner in which a gene sequence is related to its respective protein sequence is referred to as the _________ code.(a) protein(b) genetic(c) translational(d) expression5-20 Given the sequence of one strand of a DNA helix as5′-GCATTCGTGGGTAG-3′,give the sequence of the complementary strand and label the 5′ and 3′ ends.5-21 When double-stranded DNA is heated, the two strands separate into single strands in a process called melting or denaturation. The temperature at which half of the duplex DNA molecules are intact and half have melted is defined as the