L.T 6.1 DNA Transcription & Translation

Central Dogma of Molecular Biology (Gene & Protein relationship)

Genes affect proteins, but vice versa doesn’t occur.

Central Dogma of Molecular Biology (RNA usage)

RNA is utilized to translate the genetic code of DNA (nucleotides) into proteins (long amino acid chains).

mRNA

Short for Messenger RNA. Transcribes a gene’s genetic code from DNA.

What does mRNA read?

Reads the two subunits of rRNA to translate.

mRNA codons

3-base long codons are on mRNA. Codes for amino acids.

rRNA

Short for Ribosomal DNA. Composed of two subunits.

rRNA subunits

30S and 50S. Made of nucleotides and proteins.

Three binding sites of 50S

Amino Acyl, Peptidyl, Exit Site

Amino Acyl

Provides the landing point for tRNA to drop off the appropiate amino acid.

Peptidyl

Second site; holds tRNA with growing protein chain.

Exit Site

Stage where the tRNA that just released the protein leaves to find more of its own amino acids.

tRNA

Short for transfer RNA. Small and made of nucleotides.

What nucleotide is in RNA instead of thymine?

Uracil

Why is uracil in RNA but not DNA?

Uracil is less stable and is safely able to be used in RNA. DNA requires thymine as it is more stable for long term storage.

DNA transcription

Process where a gene (part of DNA) from a single strand of DNA is utilized as a template to make a strand of mRNA that’s a copy of a gene from DNA.

Polypeptide

The amino acid chain that an mRNA strand “reads” and translates into.

Codon vs anticodon location

tRNA has anticodons, mRNA has codons.