GCD Group Problems Test with Complete Solutions

GCD Group Problems Test with Complete Solutions 1. From their experiments, Hershey and Chase concluded that the genetic material of T2 is DNA. Were there data consistent with the genetic material being RNA? If so, how could they have experimentally distinguished between DNA and RNA as the genetic material? You can assume that they had all types of radiolabeled bases (A, T, G, C and U) at their disposal. - Answer-Hershey and Chase used 32P, a radioisotope of phosphorus, to label DNA in T2 Phages. However, RNA also use phosphates to form a "backbone" for the strand. Because of this, their conclusion was consistent with the genetic material being RNA as well as DNA. If they had radiolabeled their bases, they could have compared the amount of Thymine with the amount of Uracil. If RNA was the genetic material of Phages, there would have been no Thymine present. If DNA was the genetic material, there would have been no Uracil present. RNA also contains a different type of sugar (ribose), while DNA contains deoxyribose. RNA is also only single stranded. Only in some places does an RNA molecule fold and create a double helix. Because of this, an experimenter could use X-ray diffraction to see if the 3-dimensional shape shows a complete double helix DNA or a single stranded RNA (possibly with sections of double helix). 2. What are the key structural features of the DNA double helix? Describe how those structural features are important with regard to the four features that the genetic material must fulfill? The primary function of DNA is to store and transmit genetic information. A DNA molecule is made up of a few small building blocks, which gives the DNA its structure. First it is composed of nucleotides, which are repeating nitrogen bases linked together with phosphate groups and deoxyribose, a pentose sugar. The phosphate groups and sugar form the "backbone" of the DNA strand. These nucleotides are linked together to form a strand of DNA. Because of the way they link, the phosphates connect each 5' carbon of a sugar molecule to the 3' carbon of the next down the line. - Answer-This assures that the strand has directionality, which aids in DNA replication, and allows the duplication of cells and the transmission of DNA from parent to offspring. Four nitrogen bases combine in different sequences to code for proteins. A double helix will be formed when two strands of DNA interact with each other. Furthermore, the folding and bending of a DNA double helix results in a three-dimensional structure