Weathering and erosion. Weathering is the process where rock is dissolved, worn away or broken down into smaller and smaller pieces. There are mechanical, chemical and organic weathering processes.
What is trinucleotide repeat disorders? A class of genetic diseases that causes expansion of the number of trinucleotide (three base repeats of CG-rich units) within a gene sometimes associated with deleterious consequences.
Proliferating tricholemmal tumor (PTT), also known as proliferating pilar tumor or pilar tumor, is a well-circumscribed proliferation of squamous cells [18, 19]. It commonly occurs on the scalp or other parts of the head and neck as a gradually enlarging nodule or tumor (Figure 17).