Final answer:
Facilitated diffusion is a type of passive transport where substances move down concentration gradients through specific membrane proteins without energy consumption, with glucose transport being a common example.
Step-by-step explanation:
Facilitated Diffusion refers to the process where substances move down their concentration gradients through membrane proteins without the use of cellular energy. This movement is crucial for molecules that cannot freely pass through the lipid bilayer of the cell membrane due to their size, charge, or polarity.
For instance, glucose, a vital nutrient for cellular respiration, enters cells by facilitated diffusion using a specific carrier protein known as a glucose transporter.
This process does not require energy, distinguishing it from active transport mechanisms in cells. Furthermore, facilitated diffusion can occur through channel proteins or carrier proteins that are either selective or less selective depending on their structure.