Gene Expression (KA3)

Key Area 3

Describe the process of transcription

RNA polymerase creates a complementary strand of mRNA from the DNA template producing a primary transcript

Describe the role of tRNA during translation

Carries a specific amino acid to the ribosome

Explain how the base sequence of a gene determines the amino acid sequence of a protein

Three bases on mRNA are codons these codons will code for a specific animo acid

Describe the structure features of tRNA

tRNA has anticodon and animo acid attachment site

State what is meant by an intron

A non coding region of DNA

State what it meant by an exon

A coding region of DNA

Name the process that the mature transcript during translation

RNA splicing

State the function of messenger RNA (mRNA)

Carries a complementary copy of DNA from the nucleus to a ribosome

State the role of mRNA in gene expression

Carries a complementary copy of DNA from the nucleus to a ribosome

State the role of tRNA in gene expression

Carries a specific amino acid to the ribosome

State the role of rRNA in gene expression

Makes up parts of the ribosome along with proteins

Name of the enzyme that breaks bonds between bases in DNA during transcription and synthesises mRNA

RNA polymerase

How are different forms of proteins be made from one gene

Alternative RNA splicing

What are the two stages of gene expression

Transcription and translation

What are the bases in RNA

Adenine, uracil, guanine, cytosine

Explain how alternative RNA splicing can allow different proteins to be produced from the same gene

Different combinations of exons are retained in the mature transcript

During RNA splicing, what happens to introns

They are removed from the primary transcripts

During RNA splicing, what happens to exons

They are retained and joined together to form the mature transcript

Name the process in which mRNA is produced from a DNA template

Transcription

Describe what happens to the primary transcript during RNA splicing

Introns are removed while exons are joined together to form a mature transcript

State the type of bond that joins amino acids together in a protein

Peptide bonds

Describe the process of alternative RNA splicing

Different exons are joined together in the mature transcript