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.
Any employer can set up a profit sharing plan, according to the IRS Retirement Plans Navigator. When combining contributions from employees and employers, a 401k can allow annual contributions of up to $49,000 total, or 100 percent of the employees&#039; compensation, whichever is less. For a profit sharing plan, the maximum contribution is the same $49,000 or a lower 25 percent of an employee&#039;s salary.