Question

complete the table to compare the three types of passive transport. simple diffusion facilitated diffusion osmosis molecules cross the membrane through the phospholipids molecules cross the membrane through proteins molecules move down their concentration gradient molecules move without using cellular energy

Explanation:

Step1: Understand simple diffusion

Simple diffusion is the movement of small, non - polar molecules (like oxygen and carbon dioxide) directly through the phospholipid bilayer of the cell membrane. It does not require proteins and moves down the concentration gradient without using energy.

Step2: Understand facilitated diffusion

Facilitated diffusion involves the movement of larger or polar molecules (such as glucose) across the membrane with the help of transport proteins (carrier or channel proteins). It also occurs down the concentration gradient and is a passive process.

Step3: Understand osmosis

Osmosis is the diffusion of water across a semi - permeable membrane. Water can move through aquaporins (protein channels) or directly through the membrane in some cases. It is a passive process that occurs down the water potential gradient (related to solute concentration gradient).

Answer:

	simple diffusion	facilitated diffusion	osmosis
molecules cross the membrane through proteins	No	Yes	Yes (water - specific channel proteins called aquaporins)
molecules move down their concentration gradient	Yes	Yes	Yes
molecules move without using cellular energy	Yes	Yes	Yes