Exam 5: The Working Cell

White blood cells (WBCs)are more resistant to lysis than red blood cells (RBCs). When looking at a sample of blood for WBCs, what could you do to reduce interference from RBCs?

An energy barrier

Relaying a message from a membrane receptor to a molecule that performs a specific function within a cell occurs when

Figure A. Changes in permeability of tubules in the kidney in response to the hormone vasopressin (AVP), which aids in osmoregulation. Figure B. Density of aquaporins in kidney tubule cells before, during, and after administration of vasopressin. Figure C. Permeability of tissues to water before, during, and after administration of vasopressin. The following questions relate to these data indicating how the tubules in the kidney respond to the administration of the hormone vasopressin. -How do the data in Figure A relate to the data in Figures B and C?

Heating inactivates enzymes by

Many physiological conditions are related to particular proteins in cell membranes. The number of insulin receptors in membranes is related to the amount of insulin present around those cells. If the presence of increased insulin results in a decrease in receptors and a decrease in insulin results in an increase in insulin receptors, this would be an example of

Which of the following statements about the ATP molecule is true?

Most of a cell's enzymes are

After reading the paragraph below, answer the questions that follow. Americans spend up to $100 billion annually for bottled water (41 billion gallons). The only beverages with higher sales are carbonated soft drinks. Recent news stories have highlighted the fact that most bottled water comes from municipal water supplies (the same source as your tap water), although it may undergo an extra purification step called reverse osmosis. Imagine two tanks that are separated by a membrane that's permeable to water, but not to the dissolved minerals present in the water. Tank A contains tap water and tank B contains the purified water. Under normal conditions, the purified water would cross the membrane to dilute the more concentrated tap water solution. In the reverse osmosis process, pressure is applied to the tap water tank to force the water molecules across the membrane into the pure water tank. -Water that is filtered out of the blood by the kidneys is returned to the body through the action of aquaporins. Which of the following statements about water balance disorders is scientifically accurate?

What is the basic difference between exergonic and endergonic reactions?

The active site of an enzyme is

Which of the following statements regarding enzyme function is false?

Which figure depicts an animal cell placed in a solution hypotonic to the cell?

A child is brought to the hospital with a fever of 107°F. Doctors immediately order an ice bath to lower the child's temperature. Which of the following statements offers the most logical explanation for this action?

How does inhibition of an enzyme-catalyzed reaction by a competitive inhibitor differ from inhibition by a noncompetitive inhibitor?

Which of the following processes can move a solute against its concentration gradient?

Which of the following direct energy transfers is impossible in living systems?

Substrates bind to an enzyme's ________ site.

A man with a dirty cut on his hand appears at the emergency department for treatment. In order to clean the wound, the health-care provider should use

Which of the following is a typical feature of an ATP-driven active transport mechanism?