1. To be selectively or semi-permeable means that a membrane allows certain substances to pass through while blocking others. This selectivity is based on factors like size, charge, and solubility.
2. Passive transport is the movement of molecules across a cell membrane without the use of cellular energy (ATP). It relies on the concentration gradient, where molecules move from an area of higher concentration to an area of lower concentration.
3. The three types of passive transport that occur in the body are diffusion, osmosis, and facilitated diffusion.
4. Facilitated diffusion is the movement of molecules across the membrane with the aid of a transport protein. The structure that assists this process is a transport protein (such as a channel protein or carrier protein).
5. The overall goal of diffusion, osmosis, and facilitated diffusion is to achieve equilibrium, where the concentration of molecules is equal on both sides of the membrane.
6. Diagram(s) that show that the cell will shrink: C
7. Diagram(s) that show that the cell will swell: B
Parent Tip: Review the logic above to help your child master the concept of diffusion and osmosis worksheet.
