Answer:
d. Humans and other animal hosts lack peptidoglycan cell walls.
Explanation:
Humans and other animals lack cell walls. Bacterial cells have peptidoglycan cell walls around them. The absence of cell walls in the cells of human and other animal host ensures that these cells are not affected by the drugs that target the peptidoglycan cell walls to kill or slow down the growth of the bacterial pathogen.
This makes the drugs specifically target the bacterial cells only while not affecting the host cells. If a drug would target a component present in cells of both the pathogens and hosts, the host cells would be most likely to be harmed by the drugs.
Answer:
A. The smooth, clear rock layers
Explanation:
Adaptation is the correct answer
Answer:
D. Separate ecosystems can affect each other.