Question

question 2
2 pt
why are lipids and proteins free to move laterally in membranes?
the interior of the membrane is filled with liquid water.
lipids and proteins repulse each other in the membrane.
phospholipids form hydrogen bonds with water at the membrane surface, which moves the lipids as water moves.
weak hydrophobic interactions in the interior of the membrane are easily disrupted.

Explanation:

The fluid mosaic model of the cell membrane states that membranes are composed of a phospholipid bilayer with embedded proteins. The phospholipids have hydrophobic tails that interact weakly with each other. These weak hydrophobic interactions in the interior of the membrane are easily disrupted, allowing lipids and proteins to move laterally.

• Option 1: The interior of the membrane is hydrophobic (due to fatty acid tails of phospholipids), not filled with liquid water.
• Option 2: Lipids and proteins do not repulse each other in a way that causes lateral movement. Proteins are embedded in the lipid bilayer.
• Option 3: Phospholipids form hydrogen bonds with water at the membrane surface (hydrophilic heads), but this does not directly cause lateral movement of lipids as water moves. The key is the nature of interactions in the membrane interior.

Answer:

Weak hydrophobic interactions in the interior of the membrane are easily disrupted.