Qualifications for doing ms in german.?

Am doing B.tech/ Biotechnology. I wish to do my ms in germany. Wat is the minimum marks required for doing ms and wat are all the qualifications for doing ms? Should i need to write toefl or gre? Wat are all the universities giving ms under biotechnology? May i need the list of top most universities and wat are marks for each universities? Kindly answer me.............