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.
For example, someone may experience depression right after their family member has been diagnosed with Alzheimer's. Other caregivers may experience it as Alzheimer's progresses and the cognitive abilities of the person with Alzheimer's diminish. Signs and symptoms of depression include: Becoming easily agitated or frustrated. Feelings of worthlessness or guilt.