Molecular Diagnostics; Exam 1 Revised [100% PASS] /verified/

Molecular Diagnostics; Exam 1 Revised [100% PASS] /verified/ 3 common parts of a nucleotide *Ans* 1) 5 carbon sugar 2) phosphate group 3) nitrogenous base Purines *Ans* Adenine & Guanine Pyrimdines *Ans* Cytosine, Uracil, and Thymine Nucleotide subunits are linked together by *Ans* Phosphodiester bonds List three structural differences between DNA and RNA *Ans* 1) on the sugar: RNA has an OH on the 2' C (ribose). DNA has an H on the 2' C (deoxyribose) 2) Nitrogenous base: RNA uses Uracil instead of Thymine 3) RNA is typically single stranded, DNA is double stranded What is the overall charge of DNA and where on the structure does it come from? *Ans* Negatively charged- this is due to the oxygen on the phosphate backbone What is the difference between the leading and the lagging strand in DNA replication? *Ans* -Leading strand is the continuous strand that copies in the 5' to 3' direction of the opening double helix -Lagging strand discontinuosly copies the DNA in the 5' to 3' direction on the stran moving in the opposite direction of the opening double helix. This generates Okazaki fragments What enzyme opens up the two strands of DNA? *Ans* helicase Which direction is a DNA sequence always written *Ans* 5'-3' direction. If it was not standardized this would lead to incorrect interpretation of protein sequences and presentation of sequence data. What is a plasmid, and how does it differ from chromosomal DNA? *Ans* A plasmid is an extrachromosomal (not extraneous), circular piece of DNA found in bacteria. They cary genes that help bacteria survive in a wide range on environments. Write the complimentary sequence: 5' ATTGGCC 3' *Ans* 5' GGCCAAT 3' What is Ethidium Bromide? *Ans* an "intercalating agent" a flourescent dye that binds DNA Denaturing agents *Ans* -formamid