Why do freshwater fish excrete a large amount of very dilute urine?
a. Because they live in a hypoosmotic solution, their cells take up excess water that must be excreted.
b. Because they live in a hypoosmotic solution, their cells tend to accumulate a lot of solute that must be excreted.
c. Because they live in a hyperosmotic solution, their cells take up an excess of water that must be excreted.
d. Because they live in a hyperosmotic solution, their cells tend to accumulate a lot of solute that must be excreted.
e. Because animals must live in an isoosmotic solution, they excrete solutes to make the concentration of solutes in the water equal to the concentration of solutes in their cells.
Answer: a. Because they live in a hypoosmotic solution, their cells take up excess water that must be excreted.
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A human host can prevent a pathogen from getting enough iron by all of the following except
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