You've probably answered your question by now. But the answer: Yes. I can't speak to modern Greek, but if you're talking about ancient Greek, verbs come from six principal parts
- present active indicative
- future active indicative
- aorist active indicative
- perfect active indicative
- perfect middle/passive indicative
- aorist passive indicative
Every single verb form or participle is derived from the "tense stem" of one of the above. Therefore, it's important that you memorize all when learning a Greek verb, especially if there are any irregularities. It's especially important as many of the very common verbs derive from multiple roots. Let me know if you have a follow-up question.