Progesterone. Print | Email article to a friend | Last updated: January 14, 2015. Progesterone is a hormone released by the corpus luteum in the ovary. It plays important roles in the menstrual cycle and in maintaining the early stages of pregnancy. It may also be involved in the growth of certain cancers.
Maple helicopters fall before the leaves drop from the trees. Maple trees (Acer spp.) produce winged seeds called double samaras, which twirl to the ground in late summer or early fall. They resemble helicopters in motion, earning them the common name of helicopters or whirligigs.
Maple Tree Diseases. Top 4 Maple Tree Diseases. If you have maple trees that are starting to look battered, it may have caught one of many maple tree diseases. Maple trees are beautiful and can really spice up an otherwise boring yard. These trees can grow up to 145 feet and can be recognized by there leaves.