3.1.5 Nucleic acids are Important Information-Carrying Molecules Flashcards
Basic function of DNA and RNA
DNA is to store genetic information
RNA transfers information to ribosomes
Components of a nucleotide
Phosphate group
Penrose sugar (for DNA, deoxyribose and for RNA, ribose)
Nitrogen containing carbon base (for DNA, A,T,G,C and for RNA, A,U,G,C)
Explain 5’3’ prime direction
- Phosphate binds to 5th carbon of penrose sugar
- Next nucleotide joins to 3rd carbon of penrose sugar
- Condensation recation occurs
- Phosphodiester bond is formed
- Appropriate enzyme, DNA/RNA polymerase
How many hydrogen bonds form between base pairs A,T and A,U
2 hydrogen bonds
How many hydrogen bonds form between base pairs G,C
3 hydrogen bonds
Describe the structure of ribonucleic acid (5)
- Polymer of nucleotides
- Pentose sugar is ribose
- Organic bases are A,U,G,C
- mRNA = single stranded, linear polynucleotide, it’s a single stranded copy of a gene and takes information to the ribosome
- tRNA = single stranded polynucleotide coded into cloverleaf shape, brings amino acids to ribosome during protein synthesis
- rRNA = found in the ribosomes along with protein
Provide the function of: sugar phosphate backbone
- Provides strength and stability
- Protects information coded in bases and hydrogen bonds
Provide the function of: DNA being a longer molecule
Holds lots of information
Provide the function of: DNA having a helix structure
Compact
Provide the function of: DNA having a base sequence
Codes for amino acids and therefore proteins
Provide the function of: DNA being double stranded
Allows SCR - each strand acts as a template
Provide the function of: DNA having complementary base pairing
Accurate replication
Provide the function of: DNA having weak hydrogen bonds between bases
Easily broken in SCR
Provide the function of: DNA having many hydrogen bonds
Strong and stable
The double helix
2 polynucleotide chains held together by hydrogen bonds between complementary base pairs