Unit 1-Gene Expression Flashcards
Gene expression is made up of which two processes
Transcription and translation
Process that converts DNA into primary mRNA transcript.
Transcription
Synthesis of a polypeptide chain from mRNA.
Translation
Section of RNA removed to create the mature mRNA transcript.
Introns
What does the messenger RNA (mRNA) do?
Carries a copy of the DNA code from the nucleus to the ribosome.
What does the transfer RNA (tRNA) do?
Carries its specific amino acid to the ribosome
Sugar molecule present on RNA
Ribose
What is the ribosome made of?
Ribosomal RNA and proteins form the ribosome.
Type of base present in RNA rather than thymine in DNA.
Uracil
The 20 subunits that make up a polypeptide.
Amino acids
First mRNA transcript made before processing
Primary mRNA transcript
Three types of RNA involved in transcription and translation
messenger (mRNA), transfer (tRNA) and ribosomal (rRNA)
Where translation takes place
Ribosome
Fragments of mRNA which join together to form the mature transcript.
Exons
Triplets of bases on mRNA each of which codes for an amino acid.
Codon
Triplet of bases on a tRNA molecule which determine the particular amino acid joined onto the extending polypeptide chain.
Anti-codon
Codon that initiates translation from this point on.
Start codon
Codon that terminates translation at this point and does not code for an amino acid.
Stop codon
Ways that RNA differs from DNA
RNA is single-stranded while DNA is double-stranded.
RNA has a sugar called ribose while DNA has a sugar called deoxyribose.
RNA has the base uracil while DNA has the base thymine.
Type of RNA molecule that is joined to a specific amino acid.
tRNA
Final mRNA molecule ready for translation.
Mature mRNA transcript
Different orders of exons being joined together to make different proteins
Alternative mRNA splicing
Procedure to remove introns from a primary mRNA transcript leaving the mature mRNA transcript.
Splicing
A chain of amino acids linked together by peptide bonds
Polypeptide (Proteins)