3 multiple choice questions

Question

Stuck on these three for my at study guide.

1.) Which gene in an operon is INCORRECTLY matched with its function?

A.promoter - where RNA polymerase first binds to DNA

B.structural - make mRNA by transcription

C.regulator - binds to the repressor protein

D.operator - if unbound, allows RNA polymerase to bind to DNA

2.)Which statement is NOT correct about the lac operon?

A. It regulates the production of a series of five enzymes.

B.It is normally turned off if lactose is not present.

C.Lactose binds to the repressor protein and inactivates it.

D.It is an inducible system.

E.The structural genes make products that allow lactose metabolism.

3.)Your muscle and bone cells are different because _____.

A.they contain different sets of genes

B.they are differentiated

C.different genes are switched on and off in each type of cell

D.they contain different histones

E.they contain different operons

Answer 1

1) C, the product of the regulator is the repressor but it doesn't bind its own DNA secuence.

2) A, If I'm not wrong there are only 3 enzymes coded in the lac operon

3) B, they are differentiated! That's why the different tissues perform distinct functions, even though the genome in each cell is the same.

Good luck!!