The ultimate source of energy (for most ecosystems) is the sun. The ultimate fate of energy in ecosystems is for it to be lost as heat. Energy and nutrients are passed from organism to organism through the food chain as one organism eats another. Decomposers remove the last energy from the remains of organisms.
The Contribution Limit. For 2013 and 2014. the basic limit for regular contributions to a Roth IRA is $5,500 for people under 50 years of age, and $6,500 for those who are 50 or older. (Numbers like this can be found in our Reference Room.) This limit may be reduced for any of the following reasons:
Contribution Limits. The contribution limits for the Roth and traditional IRAs are the same. For tax year 2013, for example, you could contribute up to $5,500 to your IRA, plus an additional $1,000 catch-up contribution if you reached age 50 or older by the end of the tax year.Deductibility.or Roth IRAs, there is no age limit. Income Limitations. One factor that determines whether you should fund a Roth or traditional IRA is your income, which dictates your eligibility to contribute to a Roth IRA. If your income exceeds certain limit, you may not contribute to a Roth IRA.