In eukaryotes, which terms accurately reflect the nature of replication of the c
ID: 77936 • Letter: I
Question
In eukaryotes, which terms accurately reflect the nature of replication of the chromosome? a) Unidirectional with multiple origin of replication sites on a single chromosome b) bidirectional with a single origin of replication site per chromosome c) bidirectional with multiple origins of replication sites per chromosome d) unidirectional with a single origin of replication site per chromosome Why does DNA synthesis start with a RNA primer? a) DNA polymerases require a free 2'-OH group to attach the next nucleotide and that is only provided by RNA b) DNA polymerases require a free 3'-OH group to start synthesizing a new strand, but RNA erases do not c) RNA polymerases make RNA polymers faster than DNA polymerases make DNA polymers d) RNA polymerases are faster at unwinding the DNA molecule than DNA polymerases The discontinuous nature of replication occurs on the lagging strand during DNA synthesis because a) DNA is supercoiled on one strand and has a relaxed configuration on the complementary strand b) The lagging strand requires an RNA primer, which takes longer to synthesize, but the leading strand does not c) the helicase enzyme cuts the DNA in a random fashion on the lagging strand d) the 5' to 3' directionality requirement of DNA synthesis results in one new strand elongating in a direction opposite of the direction the fork is opening One complete nucleosome is comprised of: a) 147 base pairs, 2 molecules of H2A, 2 of H2B, 2 of H3 and 2 of H4 b) 147 base pairs, 2 molecules of H2A, 2 of H2B, 2 of H3 and 2 of H4, one H1, and linker DNA segment c) H1 histone and linker DNA d) 147 base pairs of DNA, 4 histone proteins, and 4 nonhistone protein. Which of the following statements about histones is FALSE: a) they are negatively charged b) due to their charge, they easily bind to DNA c) they are highly conserved evolultionarily d) the histone tails are targets of chemical modification, e.g. methylation, acetylation, phosphorylationExplanation / Answer
Answer 17. C
Bidirectional- one leading strand and other is lagging strand.
Multiple origin
Answer 18. B
The DNA polymerase can only attach them on the 3' -OH end of another deoxyribonucleotide . Primase , unlike DNA polymerase , does not require a free 3' -OH end for synthesis.
Answer 19. D
The replication occurs only in 5' to 3' direction that's why on fragment is relpicate in continuous manner while other in discontinuous.
Answer 20. B
147 bp wrapped in left handed supercoil turns around a histone octamer cobsisting 2 copies of each H2A, H2B, H3, H4 and a linker DNA.