dioxin is a chemical byproduct made during manufacturing. animal testing has shown that it can have negative effects on organisms such as birth defects, liver damage, and immune suppression. however, the effects vary greatly between species. a mouse may be able to handle a higher dose than a cat. dioxin enters a cell and binds to a receptor protein, which then attaches to the cell's genetic material. how does dioxin's mechanism contribute to its variable effects on different organisms?
a. organisms that do not require receptor proteins to initiate genetic expression are not affected by dioxin.
b. dioxin may bind to receptor proteins that inhibit expression in some genes and promote expression in others.
c. dioxin only binds to receptor proteins that affect particular genes in particular species.
d. genes that are inhibited by receptor proteins are not affected by dioxin since they are not expressed anyway.