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.
According to the IRS, certain gifts are not taxable. These include gifts that are less than the annual exclusion amount. As of 2012, a married couple can give up to $26,000 tax-free, referred to as gift splitting..If you pay tuition or medical expenses for someone, you don't have to pay tax on the money. Gifts to your spouse are also tax-free.ccording to the IRS, certain gifts are not taxable. These include gifts that are less than the annual exclusion amount. As of 2012, a married couple can give up to $26,000 tax-free, referred to as gift splitting..