Corpus luteum - Development and structure. 1  The corpus luteum develops from an ovarian follicle during the luteal phase of the menstrual cycle or oestrous cycle, following the release of a secondary oocyte from the follicle during ovulation.
Iron found in foods is either in the form of heme or non-heme iron. Heme iron is better absorbed than non-heme iron. Foods containing heme iron are the best for increasing or maintaining healthy iron levels. Such foods include (in order of iron-richness) clams, oysters, organ meats, beef, pork, poultry, and fish.
Iron in plant foods such as lentils, beans, and spinach is nonheme iron. This is the form of iron added to iron-enriched and iron-fortified foods. Our bodies are less efficient at absorbing nonheme iron, but most dietary iron is nonheme iron.1  1.ron-Rich Foods. Very good sources of heme iron, with 3.5 milligrams or more per serving, include: 1  3 ounces of beef or chicken liver. 2  3 ounces of clams, mollusks, or mussels. 3  3 ounces of oysters.