1.3 Gene Expression Flashcards
(25 cards)
What are the non coding regions of genes?
Introns
What are the coding regions of genes?
Exons.
What is gene expression controlled by?
Transcription and translation.
What is gene expression influenced by?
Insta-cellular and extra-cellular environmental factors.
Why are genes expressed?
Genes are expressed to produce proteins.
What are proteins formed from?
Proteins are formed from polypeptides.
What are polypeptides?
Polypeptides are chains of amino acids held together by peptide bonds
What kind of bonds are polypeptides held together by?
Peptide bonds
What base replaces Thymine in gene expression?
Uracil
In transcription, which enzyme moves along unwinding the DNA double helix?
RNA Polymerase
What enzyme aligns RNA nucleotides by complementary base pairing to form a primary transcript?
RNA Polymerase
When introns are removed and the exons are spliced together what does this form?
A mature mRNA transcript
What process allows different mRNA’s to be formed from the same primary transcript?
Alternative RNA Splicing
What are triplets of bases called?
Codons
What does the translation of mRNA result in?
The production of a polypeptide
What do codons code for?
Specific amino acids
What do start and stop codons do?
Start and stop translation
What are ribosomes made from?
Ribosomes are made from ribosomal RNA (rRNA) and proteins
What is the role of mRNA?
mRNA carries a copy of the DNA code to the nucleus from the ribosome where it is translated.
What is the role of rRNA?
rRNA makes ribosomes and proteins.
What is the role of tRNA?
The role of tRNA is to transfer specific amino acids to the mRNA on the ribosomes.
What are the amino acids carried by?
Amino acids are carried by specific tRNA molecules
What do tRNA anticodons align with?
tRNA anticodons align to their complementary codons on mRNA.
Once the tRNA molecules deliver amino acids in sequence, these are joined by what kind of bonds to form what?
Joined by peptide bonds to form polypeptides.
