then the system is called a severe tropical cyclone. These are referred to as hurricanes or typhoons in other countries. The circular eye or centre of a tropical cyclone is an area characterised by light winds and often by clear skies. Eye diameters are typically 40 km but can range from under 10 km to over 100 km.hen the system is called a severe tropical cyclone. These are referred to as hurricanes or typhoons in other countries. The circular eye or centre of a tropical cyclone is an area characterised by light winds and often by clear skies. Eye diameters are typically 40 km but can range from under 10 km to over 100 km.
A UCLA Health answered. Alzheimer's disease affects the brain. The disease causes degeneration of brain tissue and nerve cells. With less nerve cells present, it becomes harder for the brain to communicate with the body and function properly. Specifically, the neurotransmitter (a chemical that passes among cells relaying messages) acetylcholine isn't produced at a high enough volume.
However, scientists are now realizing that many other cellular changes occur in the brain during the Alzheimerâs disease process. For example, glial cells show abnormalities, as certain populations of glial cells begin to swell up and divide to produce more glial cells.