DNA Structure and Function TGT - Questions

DNA Structure and Function TGT – Questions 2 Name the three subunits that make up a DNA nucleotide. 3 Explain why a molecule of DNA is said to be antiparallel. 4 Name the two nitrogen bases that are purines. 5 Define complementary base pairing. 6 Give a structural difference between a purines and a pyrimidines that would help you differentiate one from the other. 7 What type of bond holds nitrogen bases/complementary pairs together in a molecule of DNA? 8 Complementary base pairing occurs between what two general types of molecules? 2 The bonds that hold the nitrogen bases are weak bonds, and yet a molecule of DNA is highly stable. Why is this molecule stable? 3 What is a phosphodiester bond? 4 Describe what semiconservative replication is. 5 Describe the role of DNA helicase in DNA replication and what does it do to accomplish this. 6 Describe the role of single-stranded binding proteins (SSBs) in DNA replication. 7 Define replication fork. 8 Define a replication bubble. 9 Describe the role of DNA polymerase III in DNA replication. 2 What does DNA polymerase III require to begin and describe why this is necessary. 3 Describe the role of RNA primase in DNA replication. 4 Define leading strand. 5 Define lagging strand. 6 Define Okazaki fragments. 7 Describe the role of DNA polymerase I in DNA replication. 8 Describe the role of DNA ligase in DNA replication. 9 Why are there not two leading strands in DNA replication? 2There are multiple origins of replication in eukaryotes during DNA replication. Why is this necessary? 3 Describe what it means that each parent strand acts as a template during replication. 4 Name the two scientists that are credited with determining the structure of the DNA molecule. 5 Which two scientists are credited with determining the type of replication used in DNA replication? 6 What was the conclusion of Hershey and Chases research? 7 What is the difference between continuous replication and discontinuous replication? 8 Explain why DNA can be classified as a polymer. DNA Structure and Function TGT – Answers 2 phosphate group, deoxyribose sugar, nitrogen base 3 the two strands that make up DNA’s structure run in opposite directions; one strand runs in the 5’ to 3’ direction while the other runs 3’ to 5’ 4 adenosine and guanine 5 when a nucleotide pairs with it’s specific complementary nucleotide; A’s only with T’s and C’s only with G’s 6 purines have two rings as part of their structure and pyrimidines have only one ring 7 hydrogen bases 8 a purine and a pyrimidine 2 when there are a lot of hydrogen bonds, as in a molecule of DNA, collectively they form a very strong association 3 a bond between a phosphate group of a nucleotide and the deoxyribose sugar of another nucleotide 4 replication that results in each new DNA molecule containing one parent strand and one newly synthesized strand 5 unwinds the DNA double-helix; disrupts the hydrogen bonds holding the two strand together 6 bind to each parental DNA strand, preventing the strands from rejoining 7 the region where the two unzipped portions of the DNA meets the zipped portion of DNA molecule and replication is occurring 8 a region composed of two replication forks where DNA replication is occurring 9 to synthesize new DNA strands by adding nucleotides 2 requires a 3’ of a nucleotide because it adds new nucleotides in a 5' to 3' direction 3 adds a RNA primer with a 3’ end so that DNA polymerase can begin synthesizing new DNA strands 4 the new strand of DNA that is synthesized continuously towards the replication fork 5 the new strand of DNA that is synthesized discontinuously away from the replication fork in short fragments, which are then later joined 6 short fragments of DNA, later joined, that form on the lagging strand 7 remove the RNA primer and replace them with DNA nucleotides 8 to join DNA fragments together 9 strands are synthesized in the 5’ to 3’ direction. There is only one strand that can allow this, the other strand must be synthesized discontinuously 2 it speeds the replication process up 3 each new strand is made from the parent strand 4 Watson and Crick 5 Meselson and Stahl 6 DNA is the hereditary material 7 continuous means that the new DNA strand is made in one elongating segment, nucleotides are continuously added on to the new strand; discontinous means that the new strand of DNA is made in small fragments one at a time that are joined later 8 it is made up of repeating subunits; nucleotides