this contains spoilers

Rating: Null/10 (10 October 2011)

the movie was by far one of the greatest movies i have seen today but there is something that is giving me a headache and i would like some infomation if possible
was wondering if any of you knew the answer... Why wasn't sentinal prime one of the seven primes that died to save the matrix? because i was just wondering that in the 2nd transformers it was told that there where seven primes that gave there life to protect the matrix i thought that would include Sentinal prime. but there he showed up in the third movie... why or how is this? like there are only seven original primes and sentinal was one of them correct?