JMU BIO 140 Exam 2| 335 Questions with 100% Correct Answers

JMU BIO 140 Exam 2| 335 Questions with 100% Correct Answers What occurs to the two strands of the parental duplex during replication? Correct Answer: they separate Is replication conservative, semi-conservative, or dispersive? Correct Answer: semi-conservative What does it mean to be conservative? Correct Answer: the original DNA is kept and an exact replica is made What does it mean for DNA is be dispersive? Correct Answer: parts of the old and new DNA are chopped together What does it mean for DNA to be semi-conservative? Correct Answer: each new daughter DNA is one old strand and one new strand What was the experiment that proved semi-conservative? Correct Answer: Meselsohn and Stahl experiment What was the Meselsohn and Stahl experiment? Correct Answer: -DNA was labeled with N15 to create heavy DNA -After one round of replication the parent strand still contained heavy DNA but the daughter strand contains light nitrogen - After two rounds, half of the DNA had heavy strand and a lighter strand and the other half had both lighter strands What new technology confirmed the Meselsohn and Stahl experiment? Correct Answer: fluorescent nucleotides What energy is used to add nucleotides to a daughter strand? Correct Answer: the breaking of the phosphate bonds from the nucleotide Nucleotides are added to what end of the daughter strand? Correct Answer: 3' end The template strand goes from what end to what end? Correct Answer: 3' to 5' The daughter strand goes from what end to what end? Correct Answer: 5' to 3' Where does new DNA synthesis occur? Correct Answer: replication forks How many replication forks are there in a replication bubble? Correct Answer: two The lagging strand is away or towards the fork? Correct Answer: away The leading strand is away or towards the fork? Correct Answer: towards How many DNA polymerase are used in a replication bubble? Correct Answer: 4 Replication forks are ________. Correct Answer: asymmetrical Define okazaki fragments Correct Answer: The noncontinuous segments of newly synthesized DNA along the lagging strand What are the steps of replication? Correct Answer: -unwinding of the DNA duplex -elongation occurs from 5' to 3' on the template strand -DNA polymerase extends the RNA primer -A different DNA polymerase removes the primer and replaced with DNA -fragments of the discontinuous strand are ligated with DNA ligase What does RNA primase do? Correct Answer: lays down an RNA primer How many RNA primers are on the leading strand? Correct Answer: one How many RNA primers are on the lagging strand? Correct Answer: multiple What does DNA polumerase do? Correct Answer: extends the RNA primer