If bed bugs had never been exposed to DDT in the 1950's and 1960's, how would you expect that to affect bed bugs' resistance to pyrethroids during the last decade?
A) Because bed bugs reproduce so rapidly, resistance to pyrethroids among bed bugs has become a major problem .
B) With the widespread use of DDT, pesticide-resistant mutations became much more common among bed bugs. The bed bugs passed that resistance on to future generations.
C) If some of the bed bugs carry the resistance mutations, those insects will be better able to survive and reproduce and will wind up passing the mutation on to their offspring.
D) Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals.

Babies with very low or very high weight are less likely to survive .

In a hypothetical breed of dogs, coat color is controlled by two genes. there are six different coat colors in this breed: black, brown, cream, gray, silver, and tan. consider the following crosses.cross 1: black females from a lineage of all black dogs are crossed with brown males from a lineage of all brown dogs. f1 males and females are all black. when f1 are intercrossed, f2 males and females are black or brown.cross 2: black females from a lineage of all black dogs are crossed with tan males from a lineage where all males are tan and all females are cream. f1 males are black, f1 females are gray. when f1 are intercrossed, f2 males and females are black, brown, gray, or tan.cross 3: silver females from a lineage where all females are silver and all males are gray are crossed with brown males from a lineage of all brown dogs. f1 males and females are all gray. when f1 are intercrossed, f2 males are black, brown, gray, or tan, f2 females are cream, gray, silver, or tan.select the correct statements regarding the mode of inheritance of the coat color genes.a) both genes are x-linked.b) both genes are autosomal.c) one of the genes modifies the expression of the other gene.d) each gene has an additive effect on the intensity of coat color.e) each gene independently specifies three colors.f) one of the genes is autosomal, and the other is x-linked.

Which statement about dna replication is true? a. eukaryotes only have one circular chromosome that unwinds at multiple locations. b. eukaryotes can only replicate one segment of a chromosome at a time. c. prokaryotes can only replicate their single circular chromosome in the nucleus. d. prokaryotes only have one origin of replication to initiate replication.