That is the Nucleus, the spot were all the genetic information is stored.
If the source is larger than a single point, then there's a region in the center of the shadow where the source is completely blocked and none of it is visible, and another region around the center where only part of the source is blocked and part of it is visible.
The center region is called the eye.
The umbilical region is at the center of the nine-region scheme of abdominal regions.
The center region of the retina is called the macula. this is where images are focused.
Arctic Region Supercomputing Center was created in 1993.
Basketball Center of Moscow Region was created in 1970.
A region within a larger region that is possibly different somehow.
Leishman staining is used for staining blood in microscopy and its purpose is to both identify and differentiate trypanosomas, leucocytes and malaria parasites. Giesma staining is used to stain DNA region, specifically chromosomes in order to locate aberrations like rearrangement and translocations.
For one thing, the skin around the anus represents a change from external epithelium (skin) to the internal epithelium that lines the end of the digestive tract. These layers overlap and make that small region of skin thicker. Another thing is that the epithelium surrounding the anus is more keratinised than the surrounding skin and thus appears darker.
The regional center of Region 1 in the Philippines is San Fernando City in La Union.
The pigmentation of the skin in the anal and buttocks area tends to be darker due to higher levels of melanin in that region. This is a natural variation and not necessarily a cause for concern.
B) the agricultural region