Membrane Lipid Movement

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What is the term for the movement of molecules across a membrane against their concentration or charge gradient?

Facilitated diffusion
Going against its gradient (correct)
Primary active transport
Simple diffusion

Which type of molecule can move through a membrane without any assistance?

Charged molecules
Nonpolar molecules (correct)
Polar molecules
Large polar molecules

What is the process by which charged solutes move through a protein channel without requiring energy from ATP?

Secondary active transport (correct)
Primary active transport
Facilitated diffusion
Ion channels

Which type of molecule is unable to move through a membrane?

Charged molecules (C) Signup and view all the answers

What is the term for the movement of molecules through a protein channel down their electrochemical gradient?

Facilitated diffusion (A) Signup and view all the answers

What is the result of primary active transport across a membrane?

The concentration gradient across the membrane increases (A) Signup and view all the answers

What is the term for the state of the bilayer where the interior is more fluid than solid and the acyl chains undergo much thermal motion?

Liquid-disordered state (C) Signup and view all the answers

What is the function of sterols in membrane biology?

To maintain the structure of the lipid bilayer (A) Signup and view all the answers

What is the main difference between the liquid-ordered state and the liquid-disordered state?

The organization of the acyl chains (A) Signup and view all the answers

What is the purpose of liposomes in biological systems?

To facilitate the transport of aqueous substances (A) Signup and view all the answers

What is the characteristic of the lipid bilayer in the gel phase?

The acyl chains are highly organized and have little thermal motion (A) Signup and view all the answers

What is the structure of a liposome?

A spherical sac with a bilayer of phospholipids (B) Signup and view all the answers

What is the main reason why uncatalyzed transbilayer movement of lipids is very slow?

The polar head group has to move away from a polar environment and through a hydrophobic bilayer. (A) Signup and view all the answers

What is the function of flippases in lipid movement?

To facilitate transbilayer movement of lipids. (B) Signup and view all the answers

What is the main component of the extracellular matrix (ECM) that provides structural support to surrounding cells?

Protein and sugar chains (C) Signup and view all the answers

What is the term for the movement of lipids from one side of the membrane to the other?

Transbilayer movement (D) Signup and view all the answers

What is the function of the cell membrane in relation to the intracellular matrix (ICM) and the extracellular matrix (ECM)?

To separate the ICM and ECM (D) Signup and view all the answers

What is the origin of the molecules that provide structural and biochemical support to the surrounding cells in the ECM?

Different cells that made and secreted these molecules (C) Signup and view all the answers