Imagine that you have an E. coli cell with 2 copies of the lac operon with genotype I+P+O+Z+Y+ / I-P+OCZ-Y+. What will be the expression pattern of lacZ in this cell?

a) on, only in the presence of lactose

b) always on

c) off, only in the presence of lactose

d) always off

If an female is a carrier for a Robertsonian translocation involving chromosomes 17 and 21 (17T21), what proportion of her eggs, when fertilized, would produce a child with a normal karyotype?

a) 1/4

b) 1/2

c) 2/3

d) 1/6

e) 3/4