What research method is used in order to establish what causes a behavior? an experiment What is the first step of the scientific method? pose a question In the science of human development, &quot;nurture&quot; refers to: environmental influences.
Vertical lines on one's nails, like those the writer seems to have, are a common phenomenon that often get more pronounced with age. There are many reasons for ridged nails but the most common is aging, says Dr. Phoebe Rich, M.D., FAAD, clinical adjunct professor of dermatology at Oregon Health Science University.
If you find that your toenails are flat, it can indicate that you have Raynaud's disease or a B12 deficiency. Psoriasis can cause your nails to pit. Various serious diseases cause Beau's lines and horizontal ridges, while vertical ridges can be the result of arthritis.ertical Grooves On Your Toenails. Vertical grooves can be the result of aging, iron deficiency, and kidney disorders. Rheumatoid arthritis can cause your nails to bead. Toenails that look like hammered brass can indicate hair loss. If the beds of your toenails are small and short, this can indicate heart disease.