Final Flashcards
Gene expression
Transcription. Translation. DNA directs the synthesis of proteins
Gene
Segment of DNA that codes for a protein
Transcription
Synthesizing RNA using DNA. mRNA is the messenger. Completed in the nucleus.
Translation
Synthesis of a polypeptide chain (protein). Done in cytoplasm
Codon
4 nitrogenous bases for 20 AA. Triplet code. 3 combination on mRNA. 64 possible combinations
Anticodon
Sequence of 3 nucleotides in tRNA that recognizes a triplet code in mRNA during translation. Base pairs to mRNA codon
RNA polymerase
Binds to promoter site. Sequence of DNA. Initiation sequence. Determined DNA template
Transcription factors
Collection of proteins that mediates the binding of RNA polymerase and the initiation of transcription
mRNA
Carries messages from DNA to protein synthesizing machinery of the cell
tRNA
Transfers amino acids from cytoplasm of amino acids to a growing polypeptide chain
rRNA
Together with proteins make up ribosomes. Most abundant type of RNA
Polyadenylation signal
Section of DNA read by RNA polymerase in eukaryotic cells that stops transcription of RNA
5’ cap
Guanine base complex
Poly - A tail (3’ end)
50-250 A bases. Exports mRNA from the nucleus, protects it, helps ribosomes attach to 5’ end
Introns
No coding regions. Has no genetic info. (Junk)
Exons
Coding regions. Contains genetic code
E site
Discharged tRNA’s leave the ribosome
P site
Holds tRNA carrying the growing polypeptide chain
A site
Holds tRNA carrying the next amino acid to be added to the chain
Hybridization
Mating 2 contrasting true breeding varieties
P Generation
True breeding parents
F1 generation
Hybrid off spring