Exam Questions and CORRECT Answers
Which of the following transport mechanisms may be utilized to move glucose across cell
membranes? - CORRECT ANSWER - Secondary active transport and facilitated diffusion
Which of the following statements about the Na-K pump is(are) true? - CORRECT
ANSWER - The location of the binding sites on the Na-K pump dictates the direction of
solute movement.
Examples of active transport may include __________. - CORRECT ANSWER - the
movement of Na+ ions out of cells and the movement of glucose molecules into intestinal
epithelial cells
Which of the following statements about epithelial transport in the intestines is (are) true? -
CORRECT ANSWER - The Na+/K+ ATPase is found only in the basolateral membrane of
intestinal epithelial cells and the movement of Na+ ions across the apical membrane of intestinal
epithelial cells is dependent on the electrochemical gradient created by the Na+/K+ ATPase.
Which of the following statements is false with regard to primary/secondary active transport? -
CORRECT ANSWER - Substances will always move down their concentration gradient.
If a cell were to become depleted of its ATP, which type of membrane transport would be most
directly and immediately affected? - CORRECT ANSWER - Primary active transport
Energy released by the hydrolysis of ATP is used to move K+ and Na+ across cell membranes.
This process is called __________. - CORRECT ANSWER - primary active transport
Substances that are going to move against their concentration gradient (from low concentration
to high concentration) will use which type(s) of membrane transport? - CORRECT
ANSWER - Primary or secondary active transport
, In skeletal muscle, the sarcoplasmic reticulum stores a very high concentration of Ca++. When
Ca++ is released into the cytosol of muscle to facilitate contraction, it needs to be removed and
pumped back into the sarcoplasmic reticulum so that skeletal muscle can return to its relaxed
state. The Ca++ is moved from cytosol and pumped back into the sarcoplasmic reticulum where
its concentration is much higher. What type of membrane transport does this represent? -
CORRECT ANSWER - Primary active transport
What is similar between facilitated diffusion and primary/secondary active transport? In both
forms of transport __________. - CORRECT ANSWER - a membrane transport protein is
involved
Identify which of the following is the correct definition of primary active transport. - CORRECT
ANSWER - It is mediated by a protein that directly uses ATP energy to move a substance
against its concentration gradient.
If many solutes are constantly being pumped into or out of cells, why don't the intracellular
concentrations of these solutes change? - CORRECT ANSWER - For any given solute, the
rate of active transport in one direction is equal to the passive movement (leak) of the solute in
the opposite direction.
Transport processes that can be saturated include __________. - CORRECT ANSWER -
Primary active transport, Secondary active transport, Facilitated diffusion, ion channel proteins
Which of the following will always be true of primary and secondary active transport? -
CORRECT ANSWER - At least one substance will move against its concentration
gradient.
Which of the following statements makes an accurate comparison between primary and
secondary active transport? - CORRECT ANSWER - In primary active transport ATP is
directly utilized, while in secondary active transport the potential energy of a concentration
gradient is utilized.
Transport processes that require an energy source include __________. - CORRECT
ANSWER - primary active transport and secondary active transport