Question 1

Which of the following best describes the main difference between primary and secondary active transport across the plasma membrane?

Accepted Answer

Primary active transport uses energy directly from ATP hydrolysis, while secondary active transport uses energy stored in ionic gradients created by primary active transport.

Question 2

A patient is given a drug that inhibits the Na$$^+-K$^+$$ ATPase pump. Which of the following would most likely occur as a result?

Accepted Answer

The cell would lose its ability to maintain its resting membrane potential, leading to impaired nerve and muscle function.

Question 3

Which of the following is a correct statement about the sodium-potassium pump?

Accepted Answer

It pumps 3 Na$$^+$$ ions out of the cell and 2 K$$^+$$ ions into the cell for each ATP hydrolyzed.

Question 4

Which of the following best explains why glucose can be transported into cells via secondary active transport?

Accepted Answer

The Na$$^+$$ gradient established by the Na$$^+-K$^+$$ pump provides the energy for glucose to be co-transported into the cell via a symporter.

Question 5

A white blood cell engulfs a bacterium by extending pseudopods around it and enclosing it in a vesicle. This process is best described as:

Accepted Answer

Phagocytosis

Question 6

Which of the following is NOT a function of cell adhesion molecules (CAMs)?

Accepted Answer

Directly hydrolyzing ATP to transport ions across the membrane

Question 7

During the process of exocytosis, which proteins are responsible for docking the vesicle to the plasma membrane?

Accepted Answer

v-SNARE and t-SNARE proteins

Question 8

Which of the following best describes the resting membrane potential (RMP) of a typical cell?

Accepted Answer

It is the voltage difference across the plasma membrane, typically ranging from $$-50 to$$ $$-100 mV$$, with the inside of the cell being more negative.

Question 9

Which ion is the primary determinant of the resting membrane potential in most cells?

Accepted Answer

K$$^+ ($$potassium)

Question 10

A cell is exposed to a toxin that prevents the recycling of membrane components after pinocytosis. Which process would be most directly affected?

Accepted Answer

The cell's ability to maintain its plasma membrane surface area

Question 11

Which of the following scenarios best illustrates receptor-mediated endocytosis?

Accepted Answer

A liver cell internalizes low-density lipoprotein (LDL) particles by binding them to specific receptors in clathrin-coated pits.

Question 12

Which of the following is a correct sequence of events for the process of exocytosis?

Accepted Answer

Vesicle migrates to membrane → v-SNARE binds t-SNARE → membranes fuse → contents released

Question 13

Which of the following best explains why Cl$$^-$$ ions do not significantly influence the resting membrane potential?

Accepted Answer

Their concentration and electrical gradients are balanced, so there is no net movement of Cl$$^-$$ across the membrane.

Question 14

Which of the following is an example of chemical signaling at the plasma membrane?

Accepted Answer

A hormone binds to its receptor, causing the receptor to change shape and activate a G protein.

Question 15

Which of the following best describes the role of G proteins in cell signaling?

Accepted Answer

They act as relays between extracellular first messengers and intracellular second messengers.

Question 16

A mutation causes a cell to lack functional symporters in its plasma membrane. Which process would be most directly impaired?

Accepted Answer

Secondary active transport of glucose into the cell

Question 17

Which of the following is a real-life example of transcytosis?

Accepted Answer

Transport of antibodies across the placental barrier from mother to fetus

Question 18

Which of the following best describes the function of antiporters in the plasma membrane?

Accepted Answer

They transport two different substances in opposite directions across the membrane.

Question 19

Which of the following would most likely occur if a cell's plasma membrane became equally permeable to both Na$$^+$$ and K$$^+$$ ions?

Accepted Answer

The resting membrane potential would move closer to 0 mV, reducing the cell's excitability.

Cellular Transport and Membrane Potential: Study Notes for ANP College Students

Study Guide - Practice Questions

Study Guide - Flashcards