3 - Control of Gene Expression Flashcards
The Phenotyoe is…
Organism’s visible characteristics, due to the way in which the alleles express themselves (the genotype)
What is Gene Expression?
The way in which each gene is used to synthesise a specific protein
Transcription…
Synthesis of mRNA in the nucleus, from a section of the DNA, known as a gene
Translation…
Synthesis of a polypeptide (protein) under the direction of mRNA
What does RNA stand for?
Ribonucleic acid
How does RNA differ from DNA?
1) it is single stranded
2) it has ribose sugar, instead of deoxyribose
3) it has uracil in the place of thymine
rRNA is…
Ribosomal RNA
- combines with protein to form ribosomes
tRNA is…
Transfer RNA
- provides link between mRNA and amino acids
- contains anticodon, which joins with mRNA codon
What does RNA polymerase do?
Unzips DNA double helix at region of the Gene
What is the primary mRNA transcript?
The first stage of the mRNA molecule after it separates from the DNA in the nucleus
What is the mature mRNA transcript?
The final stage mRNA, once the introns have been removed (with the exons left)
Translation occurs in…
The ribosomes (and the surrounding cytoplasm)
Where is the amino acid attachment site?
The top of the tRNA molecule
What is an anticodon?
A triplet of exposed bases at the bottom of the tRNA molecule
What are codons?
Triplets of exposed bases on the mRNA molecule