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.
Defining Characteristics. The term angiosperm derives from two Greek words: angeion, meaning vessel, and sperma, meaning seed.. The angiosperms are those plants whose seeds develop within a surrounding layer of plant tissue, called the carpel, with seeds attached around the margins.This arrangement is easily seen by slicing into a tomato, for example.owever, some current studies suggest that endosperm is not unique to angiosperms. Angiosperm flowers are generically characterized by having four whorls, or sets of organs: sepals, petals, stamens, and carpels.