$ATP \rightarrow ADP + P_i + \text{energy}$

Question 1

Which statement best describes the structure and function of the cell membrane?

Accepted Answer

It consists of a phospholipid bilayer with embedded proteins, and is selectively permeable to certain substances.

Question 2

Which type of membrane protein is primarily responsible for catalyzing chemical reactions at the cell surface?

Accepted Answer

Enzymes

Question 3

A cell is placed in a solution with a higher concentration of solutes than its cytosol. What process will occur, and what is the expected result?

Accepted Answer

Osmosis; water will move out of the cell, causing it to shrink.

Question 4

Which equation best represents the energy requirement for primary active transport?

Accepted Answer

$ATP ightarrow ADP + P_i + 	ext{energy}$

Question 5

Which of the following is an example of secondary active transport in human cells?

Accepted Answer

Na+/glucose symporter using the Na+ gradient to transport glucose against its concentration gradient

Question 6

A mutation causes the Na+/K+ pump to stop functioning. What immediate effect would this have on the cell?

Accepted Answer

The cell would be unable to maintain its resting membrane potential.

Question 7

Which organelle is responsible for the majority of ATP production in the cell?

Accepted Answer

Mitochondria

Question 8

During protein synthesis, which organelle reads the mRNA sequence and assembles the corresponding amino acid chain?

Accepted Answer

Ribosome

Question 9

Which process involves the engulfing of large particles or fluids by the cell membrane to bring them into the cell?

Accepted Answer

Endocytosis

Question 10

A patient is diagnosed with a genetic disorder affecting the cytoskeleton. Which cellular function is most likely to be impaired?

Accepted Answer

Cell movement and shape maintenance

Question 11

Which of the following best describes facilitated diffusion?

Accepted Answer

Movement of solutes down their concentration gradient through a membrane channel or carrier protein

Question 12

Which organelle is responsible for the final processing, sorting, and packaging of proteins before they are sent to their destination?

Accepted Answer

Golgi apparatus

Question 13

Which phase of the cell cycle is primarily responsible for the division of the cell's cytoplasm?

Accepted Answer

Cytokinesis

Question 14

What is the role of the smooth endoplasmic reticulum (SER) in the cell?

Accepted Answer

Stores calcium ions and synthesizes lipids

Question 15

Which of the following best explains why the cell membrane is described as 'selectively permeable'?

Accepted Answer

It allows certain substances to cross while restricting others.

Question 16

Which process is directly responsible for moving Na+ out of the cell and K+ into the cell against their concentration gradients?

Accepted Answer

Primary active transport via the Na+/K+ pump

Question 17

A cell is exposed to a toxin that blocks ATP synthesis. Which transport process will be most immediately affected?

Accepted Answer

Primary active transport

Question 18

Which of the following is NOT a function of membrane proteins?

Accepted Answer

Synthesizing DNA

Question 19

During translation, what is the role of tRNA?

Accepted Answer

It transfers amino acids to the ribosome according to the mRNA codon sequence.

Question 20

Which equation represents the movement of water across a semipermeable membrane due to osmosis?

Accepted Answer

$\Delta \Psi = \Psi_s + \Psi_p$

Cell Membrane Structure, Transport Processes, and Organelles: SEPT 11

Study Guide - Practice Questions