Which of the following is absolutely necessary for diffusion to occur?

a. a phospholipid bilayer
b. a living cell
c. a selectively permeable membrane
d. a concentration gradient


Ans: d. a concentration gradient

Biology & Microbiology

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Which statement describes evidence in support of the endosymbiont theory?

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A population of a species that is distinguishable from other populations by one or more characteristics is referred to as a(n) ________

Fill in the blank(s) with correct word

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________ is the hormone that stimulates the production of testosterone by the interstitial cells of the testis

Fill in the blank(s) with correct word

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What gives blue cheeses such as Roquefort and Stilton their unique flavor?

A) Ascomycete mold B) Alcohol C) Yeast D) Chytrids E) Mushrooms

Biology & Microbiology