TL: DNA Flashcards
Which OH group on the Deoxyribose gives up its H atom for the water molecule?
The one anti-clockwise to the O atom at the top
During the condensation reaction between the phosphate and the sugar, a water molecule is lost, what is the bond called?
A phosphate - ester link
In the condensation reaction between the sugar and the base, which molecule gives up the OH group for the water lost?
The OH comes from the sugar, the one clockwise from the O at the top
During the condensation reaction between the base and the sugar, where does the H needed for water, come from?
The only N that’s not covalently bonded to anything, and has one H atom coming off it.
A and T hydrogen bond, how many do they form and why?
They form 2.
They have the right atoms in the right places (N and H on the Adenine)
(H and O on the Thymine)
They are the right distance apart.
G and C form hydrogen bonds, how many so they form and why?
They form 3.
They have the right atoms (H H O on the Guanine)
(O N H on the Cytosine)
They are the right distance apart.
Describe DNA self replication..
- DNA Helicase breaks the hydrogen bonds and breaks the strands.
- Free floating nucleotides complementary base pair to the two open strands
- DNA polymerase joins the new nucleotides together and hydrogen bonds reform.
- You now have two DNA strands
In the sugar phosphate backbone, which molecule gives up the OH for the water molecule?
The phosphate, the OH clockwise from the P=O
Give three differences between DNA and RNA
- Ribose instead of Deoxyribose
- Uracil instead of Thymine
- Single polynucleotide strand
