Select the reason cities tended to develop at the fall line on rivers.
a)the fall line is where rivers converge, which was beneficial for trade.
b)the fall line is the widest point along the middle of a river, so travel was easier.
c)the fall line is where rivers are no longer navigable by ships traveling in from the ocean, so goods had to be offloaded.
d) the fall line follows the ridge of the appalachian mountains, providing access inland where goods could be traded.

Salmonella typhimurium is a food-borne bacterial pathogen that can cause severe gastrointestinal disease. salmonella is often phagocytosed by macrophages that normally destroy bacterial pathogens, but this bacterium is somehow able to prevent the complete maturation of phagolysosomes. salmonella is able to tolerate the low ph of phagolysosomes, and in fact responds to the drop in ph by secreting toxins that interfere with other cellular responses. which of the following differences would you expect to contribute to the survival of a bacterium within an salmonella-containing phagosome, compared to a healthy phagolysosome? decreased activity of acid hydrolases increased activity of acid hydrolases decreased import of h+ ions increased import of h+ ions my guess is decreased activity of acid hydrolases but i'm not sure.

Aeukaryotic cell must be from a plant if the cell a) a nucleus b) a nuclear envelope c) cytoplasm d) a cell wall

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?