Question 5
Question 5 of 10

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explain how gene expression may be confirmed by the use of marker genes coding for fluorescent products

describe the principles of cell signalling using the example of the control of blood glucose concentration by glucagon, limited to: • binding of hormone to cell surface receptor causing conformational change • activation of G-protein leading to stimulation of adenylyl cyclase • formation of the second messenger, cyclic AMP (cAMP) • activation of protein kinase A by cAMP leading to initiation of an enzyme cascade • amplification of the signal through the enzyme cascade as a result of activation of more and more enzymes by phosphorylation • cellular response in which the final enzyme in the pathway is activated, catalysing the breakdown of glycogen

state that transcription factors are proteins that bind to DNA and are involved in the control of gene expression in eukaryotes by decreasing or increasing the rate of transcription