In 2013, the AGI floor for someone under age 65 is 10% of AGI. The 7.5% floor applies to those 65 or older. Since it is you, and not your mom, who is taking the deduction, you must use the 10%-of-AGI floor.
An annual payment of money by a company or individual to a person called the annuitant. Payment is for a fixed period or the life of the annuitant. Tax consequences depend on the type of contract and funding.