2.1 - 2.4 Nucleic acids Flashcards
What are the 2 types of nucleic acid?
Deoxyribonucleic Acid (DNA)
Ribonucleic Acid (RNA)
Describe the structure of a DNA nucleotide
- Phosphate
- Deoxyribose sugar
- Nitrogenous base
Name the 4 DNA bases
Adenine
Thymine
Guanine
Cytosine
Describe the structure of an RNA nucleotide
- Phosphate
- Ribose sugar
- Nitrogenous base
Name the 4 RNA bases
Adenine
Uracil
Guanine
Cytosine
What is the structure of DNA?
- Double helix
- Anti-parallel nucleotide strands
- Complementary base pairing
- Phosphodiester bond between the 5’ carbon of one nucleotide and the 3’ carbon of another
- Hydrogen bonding holding DNA strands together
Name the complimentary base pairs
Adenine - Thymine
Cytosine - Guanine
What is the function of DNA?
- Store genetic information
- Allow protein synthesis
- Allows genetic info to pass from cell to cell and generation to generation
Describe the process of DNA replication
- DNA Helicase unszips the two strands by breaking the hydrogen bonds between the complementary base pairs. This allows each strand to act as a template.
- Free DNA nucleotides align with their complementary base pair on the exposed strands. They attach via hydrogen bonds (A with T, C with G)
- DNA Polymerase joins adjacent nucleoides together in a condensation reaction. This forms a phosphodiester bond between nucleotides.
- Each DNA molecule now has one new strand and one original strand. Therefore this process is called semi-conservative replication.
Describe how DNA’s sugar-phosphate backbone contributes to its function
Provides strength/stability to molecule
Describe how DNA’s length contributes to its function
Long so can store lots of information
Describe how DNA’s helical structure contributes to its function
Compact
Describe how DNA having a sequence of bases contributes to its function
Allows for very accurate replication
Describe how DNA’s double stranded structure contributes to its function
Both strands can act as templates during DNA replication
Describe how DNA’s relatively weak hydrogen bonds contribute to its function
Allows strands to be easily separated for replication or protein synthesis