Unit 1(1.3)- Gene Expression Flashcards
Where can RNA be found?
Nucleus and Cytoplasm.
What does a single nucleotide of RNA consist of?
A phosphate, a ribose and a base.
What are the four bases of RNA?
Adenine, Cytosine, Guanine and Uracil.
How do the bases in RNA pair?
Adenine and Uracil.
Cytosine and Guanine.
What are the three types of RNA?
mRNA, rRNA and tRNA.
What does mRNA do?
Carries the genetic code from DNA polymerase in the nucleus to a ribosome.
What does rRNA do?
rRNA carried proteins from the ribosome.
What does tRNA do?
Carries a specific amino acid to a ribosome.
What are amino acids in terms of proteins?
The “building blocks”
How many amino acids are there?
20
What are the two processes involved in protein synthesis?
Transcription and Translation.
Where does transcription take place?
Nucleus.
Describe the process of transcription.
Knowledge.
What is a triplet of three bases called on an mRNA strand?
A codon.
What is the non-coding region of a gene called?
Intron
What is the coding region of a gene called?
Exon
What happens to introns during transcription and what is this called?
They are removed and splicing.
What happens to the exons after the introns are removed in transcription?
They are joined together to form the mature transcript of mRNA.
What are the folds in a tRNA molecule due to?
Some base pairing of nucleotides.
What are at both ends of a tRNA molecule?
One end has a triplet of bases called an anticodon.
At the opposite end is a specific amino acid.
What are mRNA codons translated into?
A polypeptide chain.
What are the first three bases of an mRNA called?
A start codon.
What happens when the stop codon is reached in translation?
The ribosome releases the newly synthesised polypeptide chain.
What provides energy to the process translation?
ATP
What will the sequence of the codons on the mRNA strand determine?
The sequence of the amino acids in the polypeptide that will be synthesised.
What are the anticodons on the tRNA complementary to?
The codons on the mRNA strand.
What happens after a peptide bond has formed between two adjacent amino acids?
The tRNA molecule is released from, the amino acid and it then leaves the ribosome to go and pick up another one of its specific amino acids from the cytoplasm.
What happens to the proteins after translation?
It is modified.
What is gene expression controlled by?
Regulating the pr fesses of transcription and translation.
What is an organisms phenotype determined by?
The proteins produced as a result of genes being expressed.
