Types of Passive Transport Quiz

Which type of molecules can pass through the phospholipid layers of the plasma membrane via simple diffusion?

Nonpolar molecules (correct)
Large organic molecules
Hydrophilic molecules
Ions

What type of proteins are involved in the simple diffusion of ions through the membrane?

Carrier proteins
Receptor proteins
Channel proteins (correct)
Enzymes

Which process involves carrier proteins that undergo a conformational change to release molecules on the other side of the membrane?

Active transport
Endocytosis
Facilitated diffusion (correct)
Simple diffusion

Which molecules can pass through the lipid portion of the membrane easily?

Uncharged lipid-soluble molecules (A) Signup and view all the answers

Gas exchange for O2 into cells and CO2 out of cells due to concentration gradients mainly occurs in which part of the body?

Lungs (C) Signup and view all the answers

What specific channels allow water to pass through the plasma membrane in a process called osmosis?

Aquaporins (C) Signup and view all the answers

Which statement best describes the movement of water during osmosis?

Water moves from the area of low solute concentration to the area of high solute concentration. (C) Signup and view all the answers

What is the relationship between the solute concentration of a solution and its osmotic pressure?

Osmotic pressure increases as solute concentration increases. (A) Signup and view all the answers

What is the osmotic pressure of pure water?

Pure water has an osmotic pressure of zero. (A) Signup and view all the answers

What is the primary force that drives the process of osmosis?

Concentration gradient of solute molecules. (D) Signup and view all the answers

What is the purpose of osmotic pressure?

Osmotic pressure is used to describe the force required to stop osmosis. (A) Signup and view all the answers

Which of the following best describes the role of a semi-permeable membrane in the process of osmosis?

The semi-permeable membrane allows the passage of solvent molecules but not solute molecules. (D) Signup and view all the answers

What is the main function of osmoreceptors in the hypothalamus?

To stimulate the release of antidiuretic hormone (D) Signup and view all the answers

What is the main effect of a lower plasma osmolality on the osmoreceptors in the hypothalamus?

It increases the excretion of water in the urine (A) Signup and view all the answers

What is the primary role of carrier proteins in the plasma membrane?

To allow the diffusion of large or polar molecules across the membrane (A) Signup and view all the answers

Which of the following is a characteristic of carrier proteins in the plasma membrane?

They are specific to a given molecule (A) Signup and view all the answers

How does facilitated diffusion differ from simple diffusion?

Facilitated diffusion is limited by the number of carrier proteins, while simple diffusion is not (C) Signup and view all the answers

What is the primary difference between osmoreceptors and carrier proteins in the plasma membrane?

Osmoreceptors detect changes in osmolality, while carrier proteins transport molecules across the membrane (B) Signup and view all the answers

What is the primary purpose of the Na+/K+ pump?

To maintain the concentration gradient of sodium and potassium across the cell membrane (B) Signup and view all the answers

Which of the following is NOT a step in the Na+/K+ pump mechanism?

The pump releases 3 Na+ to the outside of the cell (C) Signup and view all the answers

What is the key difference between primary and secondary active transport?

Primary active transport uses ATP directly, while secondary active transport uses the sodium gradient (B) Signup and view all the answers

What is the role of the sodium gradient in secondary active transport?

The sodium gradient provides the energy needed to move other molecules against their concentration gradient (D) Signup and view all the answers

What is the primary requirement for the fusion of a vesicle with the plasma membrane?

Requires ATP (A) Signup and view all the answers

What is the purpose of the shape changes in the Na+/K+ pump mechanism?

To facilitate the binding and unbinding of the sodium and potassium ions (C) Signup and view all the answers

What is the main mechanism by which large molecules, such as cholesterol, are transported into the cell?

Receptor-mediated endocytosis (B) Signup and view all the answers

What is the primary factor that contributes to the difference in charge on each side of the plasma membrane?

All of the above (D) Signup and view all the answers

What is the role of ATP hydrolysis in the Na+/K+ pump mechanism?

To provide the energy needed to move the sodium and potassium ions (B) Signup and view all the answers

What is the term used to describe the difference in charge on each side of the plasma membrane?

Membrane potential (A) Signup and view all the answers

Which of the following is true about the membrane potential?

The membrane potential is caused by the permeability of the membrane. (A) Signup and view all the answers

What is the relationship between the membrane potential and the charge difference across the plasma membrane?

The membrane potential is directly proportional to the charge difference across the plasma membrane. (C) Signup and view all the answers