1. Water moves from an area of less concentration of solutes to an area of more concentration of solutes. Does
this mean that osmosis is a form of active transport? Explain.
2. Suppose that the concentration of Substance X is higher in the extracellular fluid (ISF) than it is within a neighboring cell. After a period of time, the concentration of Substance X inside the cell increases, and its concentration outside of the cell decreases. What must you know about Substance X to determine if it is diffusing directly through the cell membrane, or entering through protein channels?
3. A murderer deftly slips cyanide into the tea of his unsuspecting victim. The victim dies, because cyanide inhibits the production of ATP during step 3 of cellular respiration: the electron transport chain.
a. What types of membrane transport would stop, (passive transport, active transport, facilitated diffusion,
osmosis) and which would still continue to function?
b. What will happen to the intracellular and extracellular concentrations of Na+ and K+?
4. A surgery patient is mistakenly infused with an I.V. bolus that contains a solution that is hypotonic to normal human plasma. As a result, the patient dies. What might the autopsy reveal about the patient’s blood?
5. Insulin is a protein-based hormone, whereas thyroid hormone primarily made of lipids. Why is it necessary for patients to receive injections of insulin, whereas thyroid patients can take their medications orally
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