1 DNA and proteins are key molecules of the cell nucleus. 2  One gene makes one protein. 3  A gene is made of DNA. 4  Bacteria and viruses have DNA too. 5  The DNA molecule is shaped like a twisted ladder. 6  A half DNA ladder is a template for copying the whole.  RNA is an intermediary between DNA and protein.
1 Another theory holds that depression may directly damage the brain, leading to dementia. âSimply put, chronic stress and/or depression may result in the release of cortisol,â Gorman says. Over time, this stress hormone can harm the brain, she says.  A third theory points to reduced brain volume.
A. One or more conditions may cause dementia in older persons. Two common dementing conditions are Alzheimerâs Disease and stroke (sometimes called Vascular or Multi-Infarct Dementia). Alzheimer's Disease is a progressive brain disease that eventually causes severe impairment in most areas of mental functioning. EXAMPLE A person with Alzheimer's disease may have mild symptoms initially but later may not remember to use a cup for drinking or a toothbrush for brushing teeth. Eventually, the person may not recognize loved ones. Strokes cause damage (called infarcts) to one or more parts of the brain.