AP BIOLOGY

Detailed explanation-1: -Transportation through plasma membrane occurs by simple diffusion, osmosis and facilitated diffusion. These are passive transport mechanisms.

Detailed explanation-2: -There are three main types of passive transport: Simple diffusion – movement of small or lipophilic molecules (e.g. O2, CO2, etc.) Osmosis – movement of water molecules (dependent on solute concentrations) Facilitated diffusion – movement of large or charged molecules via membrane proteins (e.g. ions, sucrose, etc.)

Detailed explanation-3: -Both diffusion and osmosis are passive transport processes, which means they do not require any input of extra energy to occur. In both diffusion and osmosis, particles move from an area of higher concentration to one of lower concentration.

Detailed explanation-4: -There are three passive transportation methods-diffusion, facilitated diffusion and osmosis.

Detailed explanation-5: -Facilitated diffusion is a type of passive transport. Even though facilitated diffusion involves transport proteins, it is still passive transport because the solute is moving down the concentration gradient. Small nonpolar molecules can easily diffuse across the cell membrane.