DNA Flashcards
What is gene expression?
gene expression is the process of using information from a gene to synthesise a protein
What is a phenotype?
A phenotype is what you physically look like
What are the two stages of protein synthesis?
Transcription and translation
What is transcription?
Transcription is the synthesis of mRNA from a section of DNA
What is Translation?
Translation is the synthesis of a protein using instructions from mRNA
Where does transcription take place?
The nucleus
Where does Translation take place?
The ribosome
What order does protein synthesis occur in?
Transcription and then translation after
What number of strands does DNA have?
DNA is double stranded
What number of strands does RNA have?
RNA is single stranded
What sugar does DNA have?
Deoxyribose sugar
What sugar does RNA have?
Ribose sugar
What are the base pairs involved in DNA?
Cytosine, Guanine, Adenine,Thymine
What are the base pairs involved in RNA?
Cytosine, Guanine, Adenine, Uracil
What is mRNA function?
It carries a copy of the genetic code from the nucleus to the ribosome
What is tRNA function?
Each tRNA molecule carries its specific amino acid to the ribosome
What is rRNA function?
Forms the ribosome with proteins
What is the first step of RNA Polymerase in Transcription?
It moves along the gene unwinding the double helix and breaking the hydrogen bonds
What is the second thing RNA Polymerase does in Transcription?
It synthesises a primary transcript of mRNA from free RNA nucleotides by complementary base pairing
What is the third thing RNA Polymerase does in Transcription?
It keeps adding nucleotides from the 5’ end to the 3’ end until a stop codon is reached which results in a Primary transcript of mRNA
What are introns?
They are non-coding regions of the primary mRNA transcript and are removed
What are exons?
They are coding regions and are spliced (joined together) to form the nature mRNA transcript
What does a start codon do?
A start codon on the mRNA transcript signals for translation to begin
What does a stop codon do in translation?
Protein synthesis then stops when a stop codon is reached on the mRNA transcript
