The semimembranosus muscle does the following:
"hamstrings" - the semimembranosus muscle forms part of the hamstrings muscle group, along with biceps femoris and semitendinosus.
The muscular anatomy image shown here is in the public domain. It may have been modified by ShapeSense.com, but was originally acquired at the following address:http://en.wikipedia.org/wiki/File:Semimembranosus_muscle.PNG