Campbell Biology Chapter 11 Test Bank Study Guide Questions And Correct Answers

3) Lipid-soluble signaling molecules, such as aldosterone, cross the membranes of all cells but affect only target cells because {Ans: B) intracellular receptors are present only in target cells.}29) Which of the following is the most plausible explanation for why an animal cell would be unable to reduce the Ca2+ concentration in its cytosol compared with the extracellular fluid? {Ans: C) insufficient ATP levels in the cytosol}49) What are scaffolding proteins? {Ans: B) large molecules to which several relay proteins attach to facilitate cascade effects}54) If an adult person has a faulty version of the human analog to ced-4 of the nematode, which of the following is most likely to result? {Ans: B) a form of cancer in which there is insufficient apoptosis}58) Cells that are infected, damaged, or have reached the end of their functional life span often undergo "programmed cell death." This controlled cell suicide is called apoptosis. Select the appropriate description of this event on a cell's life cycle. {Ans: C) During apoptosis, cellular agents chop up the DNA and fragment the organelles and other cytoplasmic components of a cell.}7) Protein phosphorylation is commonly involved with all of the following except