When a pregnant woman ingests toxins such as alcohol and nicotine, the embryo is put at risk because these toxins can

1) diffuse from the mother's blood into the embryo's

blood within the placenta

2) enter the embryo when it eats

3) transfer to the embryo since the mother's blood

normally mixes with the embryo's blood m the placenta

4) enter the uterus through the mother's navel

Keeping in mind the life cycle of bacteriophages, consider the following problem: during the reproductive cycle of a temperate bacteriophage, the viral dna inserts into the bacterial chromosome where the resultant prophage behaves much like a trojan horse. it can remain quiescent, or it can become lytic and initiate a burst of progeny viruses. several operons maintain the prophage state by interacting with a repressor that keeps the lytic cycle in check. insults (ultraviolet light, for example) to the bacterial cell lead to a partial breakdown of the repressor, which in turn causes the production of enzymes involved in the lytic cycle. as stated in this simple form, would you consider this system of regulation to be operating under positive or negative control?

The nursing instructor has been observing nursing students initiate an iv infusion. which action(s), if made by the nursing student, indicates that further instruction is needed? (select all that apply.) the nursing student:

1. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 50%25%0%100% 2. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 0%100%50%25%(picture 1 is for question 1, and picture 2 is for question 2)