While limiting the expression of MHC class II to so-called “professional” APCs partially ameliorates the problem of self non self recognition among CD4+ T cells, it remains difficult to understand how it is possible that even these cells’ class II molecules are not deluged with processed “self” molecules (for example, […]

1.Which of the following would be least likely to produce long-distance water and sugar transport (bulk flow) in plants? a) negative pressure potential b) positive pressure potential c) transpiration d) diffusion assisted by aquaporins 2.All of the following are adaptations that help reduce water loss from a plant EXCEPT: a) […]

Explain how predator and prey populations control each other. Your explanation should include discussion of things like population cycles and carrying capacities. What significant differences in relative population sizes would you expect between an ecosystem where the major predator was cold blooded, and an ecosystem where the major predator was […]

Q. Eastern tent caterpillars live in large groups in silk nests, or tents that they build in trees. They are among the first insects to be active in early spring, as daily temperature fluctuates from freezing to very hot. Over the course of a day, they display striking differences in […]