Setting aside the notion of determining the number of individual animals on the planet for a moment, merely determining the number of species on the Earth is challenging. Science has only been able to offer estimates thus far, and totals vary greatly.
A. A. A. Multiple sclerosis, or MS, is a long-lasting disease that can affect your brain, spinal cord, and the optic nerves in your eyes. It can cause problems with vision, balance, muscle control, and other basic body functions. The effects are often different for everyone who has the disease.
For this reason, and because symptoms could signal any of a number of diagnoses, it is always worthwhile seeing a doctor. Alzheimer's disease is a neurological disorder in which the death of brain cells causes memory loss and cognitive decline.A neurodegenerative type of dementia, the disease starts mild and gets progressively worse.or this reason, and because symptoms could signal any of a number of diagnoses, it is always worthwhile seeing a doctor. Alzheimer's disease is a neurological disorder in which the death of brain cells causes memory loss and cognitive decline.