Diffusion Across a Cell Membrane. Diffusion is the movement of a substance across a membrane. Substances diffuse across cell membranes in a process known as passive transport. This means that the cell does not expend any energy in transporting substances across the cell membrane. Instead, substances move down their concentration gradient as a result of random thermal motion.
401k and profit sharing plans are both forms of retirement plans. They allow employees to make pre-tax contributions to an account where contributions and earnings are not taxed until distributed. Some 401k plans require an employer to make contributions to a plan.
Unlike a Pension plan, profit sharing plan contributions are not mandatory, but must be substantial and recurring. Profit sharing could account for the increase in the value of your 401(k). Investment performance could also account for the increase...or it could be a combination of both. Profit sharing plans are a type of retirement plan. In a profit sharing plan, your employer contributes some of his/her money towards your retirement. Often times, profit sharing plans are linked with 401(k) plans.