Question

The enzymes catalyzing blank and blank metabolism are produced from genes whose transcription is activated only when these sugars are present and blank has been depleted. Gene transcription from the bacterial lac operon is induced by the binding of the blank metabolite, blank, to the blank. This process opens the lac operator and blank region for blank and activates transcription. Induction of transcription of gal genes by blank is more indirect. The yeast gal genes have their transcription activated by binding of blank protein to blank elements affiliated with each gene. Blank binding is induced when it is released from blank, which is caused by the binding of blank to gal80, which occurs only when blank is bound to blank and cellular blank has been depleted.

a. Glucose, lactose, repressor, promoter, RNA synthesis, glucose, Galactose, GAL4, enhancer, GAL80, GAL3, galactose, GAL4, glucose
b. Lactose, glucose, enhancer, promoter, DNA replication, galactose, Galactose, GAL80, operator, GAL3, glucose, GAL1, GAL80, galactose
c. Galactose, lactose, operator, enhancer, Protein synthesis, galactose, Glucose, GAL3, promoter, GAL80, galactose, GAL4, GAL80, glucose
d. Glucose, galactose, promoter, operator, Protein synthesis, lactose, Galactose, GAL4, enhancer, GAL80, galactose, GAL3, GAL80, glucose

Answer 1

The enzymes catalyzing lactose and galactose metabolism are produced when these sugars are present and glucose is depleted, with lac operon activation occurring via allolactose binding and gal gene activation via a GAL4-enhancer interaction.

Step-by-step explanation:

The enzymes catalyzing lactose and galactose metabolism are produced from genes whose transcription is activated only when these sugars are present and glucose has been depleted. Gene transcription from the bacterial lac operon is induced by the binding of the lactose metabolite, allolactose, to the lac repressor. This process opens the lac operator and promoter region for RNA synthesis and activates transcription.

Induction of transcription of gal genes by galactose is more indirect. The yeast gal genes have their transcription activated by binding of GAL4 protein to enhancer elements affiliated with each gene. GAL4 binding is induced when it is released from GAL80, which is caused by the binding of GAL3 to GAL80, which occurs only when galactose is bound to GAL3 and cellular glucose has been depleted.