Why do white blood cells produces antibodies to destroy bacteria?

Your white blood cells to fight off bacteria  and viruses that make you sick.

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

answer; i believe the correct answer is (replication is not conservative);