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(a)
To determine: The base in DNA to be deaminated to form each of the bases in reference to figure 17-36a from the question.
Introduction: DNA refers to the genetic material of a cell. DNA is a double stranded structure and each strand is made up of nucleotides. A
(b)
To determine: The reason for depiction of three bases in reference to figure 17-36a from the question when DNA contains four bases.
Introduction: DNA refers to the genetic material of a cell. DNA is a double stranded structure and each strand is made up of nucleotides. A nucleotide is made up of four nitrogenous bases which are adenine, cytosine, guanine, and thymine along with a deoxyribose sugar and a phosphate group. Covalent bonds are used to join one nucleotide to the next.
(c)
To explain: The importance that the bases in reference to figure 17-36a given in the question do not occur naturally in DNA.
Introduction: DNA refers to the genetic material of a cell. DNA is a double stranded structure and each strand is made up of nucleotides. A nucleotide is made up of four nitrogenous bases which are adenine, cytosine, guanine, and thymine along with a deoxyribose sugar and a phosphate group. Covalent bonds are used to join one nucleotide to the next.
(d)
To determine: The reason that the presence of 5-Methylcytosine is likely to increase the probability of a mutation.
Introduction: DNA refers to the genetic material of a cell. DNA is a double stranded structure and each strand is made up of nucleotides. A nucleotide is made up of four nitrogenous bases which are adenine, cytosine, guanine, and thymine along with a deoxyribose sugar and a phosphate group. Covalent bonds are used to join one nucleotide to the next.
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Chapter 17 Solutions
WORLD OF CELL+MASTERING ACCESS >CUSTOM
- Number of Okazaki Fragments in E. coli and Human DNA Replication Approximately how many Okazaki fragments are synthesized in the course of replicating an E. coli chromosome? How many in replicating an “average� human chromosome?arrow_forwardHelicase Unwinding of the E. coli Chromosome Hexameric helicases, such as DnaB, the MCM proteins, and papilloma virus El helicase (illustrated in Figures 16.22 to 16.25), unwind DNA by passing one strand of the DNA duplex through the central pore, using a mechanism based on ATP-dependent binding interactions with the bases of that strand. The genome of E. coli K12 consists of 4,686,137 nucleotides. Assuming that DnaB functions like papilloma virus El helicase, from the information given in Chapter 16 on ATP-coupled DNA unwinding, calculate how many molecules of ATP would be needed to completely unwind the E. coli K 12 chromosome.arrow_forwardEthanol (CH3-CH2-OH) is miscible in water because it is able to form hydrogen bonds with itself and other molecules. However, its structure only allows it to form 1-2 hydrogen bonds. This is one reason why even low concentrations of ethanol in solution are lethal for cells. Based on this information, explain why we can use high concentrations of ethanol to precipitate DNA out of solution. Also, describe/predict the effects of increasing concentrations of ethanol in (and around) a cell on macro-molecular interactions (i.e. on weak bonds). Finally, it is possible to select for yeast that are tolerant to increased concentrations of ethanol. Give an example of a physiological change in yeast cells that might make them resistant to ethanol.arrow_forward
- Z-DNA derives its name from the zig-zag conformation of phosphate groups. What features of the DNA molecule allow this structure to form?arrow_forward5’-CCTAGACCATAACAT-3’ What happens to the amino acid sequence above as a result of each of the following mutations in the DNA: Substitution of A with T at position 4? Addition of T between positions 8 and 9? Substitution of A with T at position 11? Deletion of A at position 12? Substitution of C with T at position 7? State the type of mutation for each of the base changes indicated.arrow_forwardBoth DNA polymerase (any DNA polymerase) and ligase catalyze the formation of a bond between nucleotides, but these two enzymes do NOT catalyze the same reaction. Briefly describe the differencesbetween the reaction catalyzed by the polymerase activity of DNA polymerase and the one catalyzed by ligase.arrow_forward
- pppApCpCpUpApGpApU-OH(a) Using the straight-chain sugar convention, write the structure of the DNA strand that encoded this short stretch of RNA.(b) Using the simplest convention for representing the DNA base sequence, write the structure of the nontemplate DNA strand.arrow_forwardThe relative proportions of cytosine-guanine and adeninethymine bonds in a DNA sample can be estimated by measuring its “melting temperature,” the temperature at which half of the DNA strands have pulled apart. Samples with a high percentage of cytosine-guanine pairs have a higher melting temperature than samples with a high percentage of adeninethymine pairs. Explain why this is so, considering the nature of the bonds that hold the base pairs together (look back at as shown).arrow_forwardTick the correct statements: Remember: Tautomers are structural isomers that differ from each other based on the position of the proton(s) and their double bonds. ( ) The nitrogenous bases of nucleic acids, which contain heterocyclic and analogous nuclei, can adopt different tautomeric forms involving multiple H+ that are exchangeable depending on the medium. In DNA, spontaneous formation of smaller tautomers appears to contribute to mutagenic errors during DNA replication, while in RNA, they seem to be related to increased structural and functional diversity of enzymes and RNA aptamers (research this and confirm if it is false or real) ( ) in relation to the figure, anomer 1 has beta stereochemistry with respect to the C anomeric of the pentose, and is making an N-glycosidic bond ( ) in relation to the figure, anomer 1 has alpha stereochemistry with respect to the C anomeric of the pentose, and is making an N-glycosidic bond ( ) In general, in naturally occurring nucleosides,…arrow_forward
- Functional Consequences of Y-Family DNA Polymerase Structure The eukaryotic translesion DNA polymerases fall into the Y family of DNA polymerases. Structural studies reveal that their fingers and thumb domains are small and stubby (see Figure 28.10). In addition, Y-family polymerase active sites are more open and less constrained where base pairing leads to selection of a dNTP substrate for the polymerase reaction. Discuss the relevance of these structural differences. Would you expect Y-family polymerases to have 3-exonuclease activity? Explain your answer.arrow_forwardCalculating human genome If 1.5 percent of the human genome consists of protein-coding sequences, and the entire genome has 3.2x10^9, how many codons are there in the human genome? Remember that a codon is three nucleotides in length.arrow_forwardQuestion:- Explain why there are very few sequence-specific DNA-binding proteins that bind to the minor groove of double-stranded DNA.arrow_forward
BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning