Module 2: Nucleic Acids Flashcards
Translation process
- mRNA leaves nucleus and attaches to a ribosome on RER
- tRNA carries corresponding amino acid to mRNA
- Anti-codon ensures the correct amino acid is joined onto the polypeptide chain- requires ATP
- Adjacent amino acids join together by peptide bonds creating a polypeptide chain
- Continues until stop codon is reached
Why is the genetic code said to be degenerate
Because several different triplets code for the same amino acid
What is a gene
Section of DNA which codes for 1 polypeptide
sequence of triplets
What is a triplet
Sequence of 3 bases that costs for 1 amino acid
Process of Semi-conservative replication
- DNA double helix unwinds and unzips, breaking the hydrogen bonds. catalysed by DNA helicase.
- Exposed nucleotide bases act as a template for new DNA strand
- DNA polymerase binds nucleotides together with covalent bonds, forming the new sugar-phosphate backbone
- Results in 2 identical daughter DNA strands
Process of Transcription
- DNA strand unwinds and unzips by DNA helicase
- RNA nucleotide bases pair up with exposed bases
- RNA synthase forms covalent bonds between nucleotide bases
- mRNA strand is formed and breaks away from DNA which recipes itself up
Importance of DNA replication
Ensures genetic information is conserved accurately
Structure and functions of proteins relies on the correct sequence being copied
Checks for mutations
Structure of ATP and ADP
consists of a ribose sugar, adenine and 3 inorganic phosphates for ATP and 2 inorganic phosphates for ADP
Structure of RNA molecule
Consists of ribose sugar, nitrogenous base and phosphate group
Structure of DNA molecule
Consists of deoxyribose sugar, nitrogenous base and phosphate group
Twisting of DNA produces double helix shape
Bonded by phosphodiester bonds
