What are examples of landforms? A: The four main types of landforms are mountains, plateaus, plains and hills. A landform is defined as any natural feature on the Earth's surface, which incl... Full Answer >
Definition of leukopenia. : a condition in which the number of white blood cells circulating in the blood is abnormally low.
Osteopenia is a term to define bone density that is not normal but also not as low as osteoporosis. By definition from the World Health Organization osteopenia is defined by bone densitometry as a T score -1 to -2.5. There are many causes for osteopenia including calcium and vitamin D deficiency and inactivity.