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Properties of DNA
Concept Questions
Brown
Concept
Questions


Image #1

Image #2

Image #3

Image #4
Question #1

There are many possible mechanisms that cells could use to replicate their DNA molecules. To investigate which mechanism cells actually use, scientists exploited the property of density to separate DNA molecules in different stages of replication. (See Image #1).

In which of the links below is the difference in density of DNA molecules used to separate different kinds of DNA molecules and thus get the first evidence for the possible DNA replication mechanism?

Link-#12 Link-#63 Link-#81 Link-#44

Question #2

Nucleotide triphosphates are joined together to form new, single strands of DNA as shown in Image #2. However, the polynucleotide chain can only grown in one direction, 5' to 3'.

In which of the links below is there a discussion of polymerases (enzymes that join up nucleotides into polynucleotide chains), and the phenomenon of "one way" growth of replicating DNA molecules?

Link-#19 Link-#17 Link-#14 Link-#16

Question #3

The scientist illustrated in Image #3 carried out some very valuable research relating to DNA.

In which of the links below is his work discussed and his contribution explained?

Link-#88 Link-#82 Link-#83 Link-#85

Question #4

The scientist illustrated in Image #4 started a whole new area of polynucleotide research, but he never knew or understood the importance of the new molecules he discovered.

In which of the links below is his work discussed and his contribution explained?

Link-#22 Link-#31 Link-#42 Link-#53

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© 2002, Professor John Blamire