Question

Describe how oxygen enters the cell, and how this is distinct to how water enters the cell.

Answer 1

Oxygen is a gas and it enters the cell by the process of simple diffusion. Molecular oxygen is non-polar and it enters the cell from the region of high partial pressure to the region of low partial pressure without investing any energy. Simple diffusion doesn't requires the help of any membrane transporter.

Water enters the cell by the process of osmosis. Osmosis is the movement of water molecules from the region of high concentration to the region of low concentration through a semi permeable membrane. Since water molecules are polar in nature so they need membrane transporters to get into the cell. The channels which help in the entry of water into the cell are known as the aquaporins. Osmosis simler to the diffusion doesn't requires any energy and both are the parts of passive transport.