The cell membrane controls the traffic of molecules into and out of the cell, prevents the entry of toxic material into the cell and permits selective uptake of nutrients. which property of the membrane can this be attributed to? a) carbohydrates present on the membrane
b) lipid bilayer of the membrane
c) membrane fluidity
d) semi-permeable nature of the membrane

Which plant has a visible leaf modification that will it conserve water in extremely dry environments?

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.

I’m doing some practice exam questions for biology, and i’m not sure how to do these 3 parts to the question.