Part 1: Replication: The following represents the nucleotide sequence in the gen
ID: 197701 • Letter: P
Question
Part 1: Replication: The following represents the nucleotide sequence in the gene for a short polypeptide (protein). The strand shown is the template strand 1. Replication: Beneath the template strand above, write the nucleotide sequence for the non-template strand of this segment of DNA. Be sure to include the designation for the 3 and 5' ends. During replication of the template strand, the complementary (non-template) strand would be made from the (circle the correct answer): 2. a. right to the left b. left to the right If the DNA polymerase/replication fork moves along the DNA from the LEFT to the RIGHT replicating the DNA, the new complementary strand is made in (circle the correct answer): 3. a. one long piece b. a series of short fragments c. impossible to determine from the info providedExplanation / Answer
DNA (Deoxyribonucleic acid) act as hereditary material and it carries the genetic information from one generation next generation. From generation to generation species identity is maintained by the DNA & the genes are segments of the DNA that codes for the proteins. Based on the Chargoff’s rules and X-ray diffraction data of Wilkins and Franklins, the Double helical model of DNA was given by the James Watson and Francis Crick in 1953. They predicted that two polynucleotide chains coil to each other form a right-handed double helix, in which on DNA strand run in 5’ to 3’ direction and other in 3’ to 5’ direction. The first DNA strand whose sequence complementary to the mRNA is called template DNA strand or negative DNA strand or nonsense DNA strand and the DNA strand whose sequence is similar to the mRNA, that DNA strand is known as a coding strand or positive DNA strand or sense strand.
Question number 1:
5’-ATGGGAATTGGTTACTCATAA -3’ (non-template DNA strand)
3’-TACCCTTAACCAATGAGTATT-5’ (template DNA strand)
Question number 2: Answer is A- right to the left
At replication bubble, the non-template DNA strand synthesized discontinuously in right to the left.
Question number 3: Answer is b- a series of fragments.
The main enzyme involved in DNA replication is DNA polymerase III which can synthesize DNA in 5’ to 3’ direction only but replication showed to be bidirectional (synthesized in two directions). At replication bubble the parental DNA strand (3’ to5’ strand of DNA) on which the daughter molecules are synthesized in continuously (5’ to 3’ direction) that strand is called leading strand and other parental DNA strand (5’ to 3’ strand of DNA) on which the daughter molecules are synthesized in discontinuously in small fragments (5’ to 3’ direction) called Okazaki fragments (1000-2000 nucleotide length) that strand is called lagging strand.