Question

When will a particle enter a cell through diffusion into the cell?

O when the concentration of the substance is higher inside the cell than outside
O when the concentration of the substance is higher outside the cell than inside
O when a molecule of the substance is very large

Answer 1

A particle enters a cell through diffusion when its concentration is higher outside than inside the cell, moving down its concentration gradient via passive transport.

Step-by-step explanation:

A particle will enter a cell through diffusion when the concentration of the substance is higher outside the cell than inside. This movement occurs down the substance's concentration gradient, without the need for additional energy, in a process known as passive transport. Diffusion allows small molecules like oxygen (O2) and carbon dioxide (CO2) to enter and exit cells depending on their concentration inside and outside the cell.

Large molecules or those that are not lipid-soluble require facilitated diffusion where transport proteins assist in their movement across the cell membrane.