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.
What Causes Horizontal & vertical Ridges in Finger and Toenails Ridges in fingernails Vertical ridges sometimes appear along the length of the fingernails. Sometimes marks, discoloration or pits or grooves on a fingernail, such as those that run from side to side (known as Beau's lines), can be an indication of a nail injury or a health problem. However, in the case of vertical ridges, there is normally no reason to be concerned. These ridges look and feel like raised lines, and they run from the cuticle at the base of the fingernail to the tip. These ridges are not usually a sign of injury or a health problem but are a harmless result of ageing.