Practice Questions

Osmosis is defined as the net movement of water across a membrane driven by a water potential gradient.

Receptors are usually transmembrane integral proteins that span the membrane to receive signals.

They hypothesized that the lipid bilayer was coated on both sides by globular proteins.

According to Fick's law, the rate of diffusion is directly proportional to the steepness of the concentration gradient.

Freeze-fracture techniques show proteins distributed within the bilayer, confirming the mosaic nature.

Glycolipids act as markers for cell identification and adhesion in the extracellular matrix.

Shorter chains decrease van der Waals interactions, and double bonds create fluidity; this combination results in the highest fluidity.

Peripheral proteins are loosely attached to the surface, usually via non-covalent interactions like ionic or hydrogen bonds.

Facilitated diffusion uses transmembrane proteins to move molecules that cannot pass through the lipid bilayer directly.

The hydrophilic phosphate head and hydrophobic fatty acid tails make the molecule amphipathic.