a seed needs some things to grow like water sunlight and carbon dioxide. it also need to planted in nice soil
germinate mean to begin growing or sprouting so the second stage germinate the seed starts to grow leaves and taller
a seedling is like a little baby plant that when the seed start get taller and starts to grow leaves and grow roots
when it at the adult stage it is now old enough to reproduce and make more seed and then the plant life cycle will start all over and over again and again