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:
Roth IRA Contribution Limits for Individuals 50 or Older. For individuals that are age 50 or older the same $5,500 contribution limit across all Roth IRAs is in place. However, the IRS also allows these individuals to also contribute an additional $1,000 as catch up contributions.