A Whorl is a section of hair that grows in a circular pattern. A nape whorl is a whorl of hair that grows at the nape of the neck, whorls can also grow on one's crown.
It would affect it because if you cut the hair short the nape whorl can be seen sticking up and there is nothing you can do with it. A short cut would not look right. You have to leave the hair long...
Plain whorl has at least one ridges that makes a complete circuit. The ridge may be in the form of a spiral, oval, or any variant of a circle. It also displays a degree of symmetry. As in for Central...