|
|
Although puberty usually occurs in the early teenage years, the world's youngest parents were two Chinese children who had their first baby when they were 8 and 9 years of age.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Bisphosphonates were first developed in the nineteenth century. They were first investigated for use in disorders of bone metabolism in the 1960s. They are now used clinically for the treatment of osteoporosis, Paget's disease, bone metastasis, multiple myeloma, and other conditions that feature bone fragility.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Human neurons are so small that they require a microscope in order to be seen. However, some neurons can be up to 3 feet long, such as those that extend from the spinal cord to the toes.