Bio help me please!!?

Which of the following is true about DNA?





a It is a single-stranded molecule


b Only one of the original DNA strands acts as a template during replication.


c Both of the original DNA strands act as templates during replication.


d Its replication takes place in the cytosol.








2. A zebra cell is just about to replicate its DNA. Which of the following will happen first?





a The DNA unravels to make two strands.


b RNA attaches to DNA.


c All of the cell’s DNA attaches to proteins.


d The DNA folds over on itself to create a dense chromosome.








3. During DNA replication in a human cell, 6 billion bases must be paired properly. Which characteristic of DNA best allows for high levels of accuracy during this process?





a ion channels


b base pairing according to certain rules


c single-helix shape


d presence of ribose in the backbone

Bio help me please!!?
*** Here you go ***





1. c = both original strands used for DNA (self replication)


2. a = DNA unravel to make two strands


3. b = base pairing due to specific rules (specific base pairing)
Reply:1 C


2 A (this isn't a good answer -- have a look at replication forks, Okazaki fragments).


3 B
Reply:#1 is C - see semiconservative replication


#2 is A - again see semiconservative replication


#3 is B - see complimentary base pairing. A pairs to T and C pairs to G.