Question: where does the germination of the pollen grain take place and how

title: Germination
text: Water is required for germination . Mature seeds are often extremely dry and need to take in significant amounts of water , relative to the dry weight of the seed , before cellular metabolism and growth can resume . Most seeds need enough water to moisten the seeds but not enough to soak them . The uptake of water by seeds is called imbibition , which leads to the swelling and the breaking of the seed coat . When seeds are formed , most plants store a food reserve with the seed , such as starch , proteins , or oils . This food reserve provides nourishment to the growing embryo . When the seed imbibes water , hydrolytic enzymes are activated which break down these stored food resources into metabolically useful chemicals . After the seedling emerges from the seed coat and starts growing roots and leaves , the seedling 's food reserves are typically exhausted ; at this point photosynthesis provides the energy needed for continued growth and the seedling now requires a continuous supply of water , nutrients , and light .