Maximum DNA synthesis during the midproliferative phase of the cycle (i.e. cycle days 8â10) correlates with the maximum number of mitoses in both the stromal and epithelial endometrial cellular elements, as well as with the midproliferative peak of plasma estradiol and nuclear estradiol receptors.
Some defining characteristics of angiosperms include flowers, carpels, and the presence of endosperm, a nutritive substance found in seeds, produced via a second fertilization event. However, some current studies suggest that endosperm is not unique to angiosperms.
Angiosperms exhibit double fertilization: one sperm unites with an egg, and a second sperm with the central cell of the embryonic sac, or female prothallium. Fertilization independent of the presence of free water is one of the most important adaptations of seed plants to survival on land.he second stage of the reproductive processâkaryogamy, or the union of nucleiâoccurs within the asci. Somatogamy is a process characteristic of basidiomycetous fungi. These organisms do not form gametes or gametangia, and plasmogamy occurs when two uninuclear cells, the positive and negative primary mycelia, unite.