DNA-structure And Function

Question 1

What is DNA?

Answer 1

Deoxyribonucleic acid
Codes for the sequence of AAs In the primary restriction for protein which determines the final 3-D structure and function
Essential cells contain this and it doesn’t get damaged when being passed on
The DNA polymer is a double helix

Question 2

What is a DNA nucleotide?

Answer 2

Monomer for DNA
Made up of Doxy ribose , nitrogenous base and a phosphate group
Nitrogenous base can be guanine, cytosine, adenine + thymine
( What it looks like: pentagon, circle at top, rectangle onside)

Question 3

How is a polynucleotide formed?

Answer 3

The polymer of nucleoticle
Condensation reaction, between deoxyribose sugar + the phosphate = phosphodiester bond
strong covalent bonds so genetic code is not broken down.
Sugar phosphate backbone

Question 4

How is the double helix structure formed?

Answer 4

DNA polymer occurs in pairs.- h-bonds between bases.
Two chains twist = double helix
Only C and G then A and T-complementary base pairs
AT can firm 2 H bonds
CG can form 3

Question 5

How the structure relates to function?

Answer 5

Stable structure—> sugar phosphate backbone and double helix
Double stranded so replication can occur using one strand as a template
Weak hydrogen bonds for unzipping of the two strands in a double helix during replication
Large molecules to carry lots of info
Complementary based pairing allows identical copies to be made