Structure of DNA and RNA

what is DNA

Deoxyribonucleic acid

what is RNA

Ribonucleic acid

DNA function

holds genetic information

RNA function

transfers genetic information

what forms ribosomes?

RNA and proteins

What do RNA and proteins form?

Ribosomes

Formation of nucleotides:

pentose sugar

nitrogen containing organic base

phosphate group

nucleotide

DNA nucleotide

pentose: deoxyribose

base: adenine, guanine, cytosine, thymine

phosphate group

RNA nucleotide

pentose: ribose

base: adenine, guanine, cytosine, uracil

phosphate group

how are polynucleotides formed?

condensation reaction between the phosphate group of one nucleotide and the pentose sugar of another, forming a phosphodiester bond.

how is a phosphodiester bond formed?

condensation reaction between the phosphate group of one nucleotide and the pentose sugar of another.

A strong covalent bond to ensure the genetic code is not broken down.

Formation of a DNA molecule:

2 polynucleotide chains

form a double helix

held together by hydrogen bonds between complimentary base pairs

Formation of RNA:

single stranded short polynucleotide chains

Which complementary base pairs can hydrogen bonds form between?

addnine and thymine (2 hydrogen bonds)

cytosine and guanine (3 hydrogen bonds)

how structure relates to the function:

Stable structure due to phosphodiester bonds and the double helix.

Double-stranded so replication can occur using both strands as a template.

Weak hydrogen bonds for easy unzipping of the two strands in a double helix during replication

A large molecule to carry lots of information.

Complementary base pairing allows identical copies to be made.