Spindle fibers are protein structures that form early in mitosis, or cell division. They consist of microtubules that originate from the centrioles, two wheel-shaped bodies located in the centromere area of the cell. The centromere is also known as the microtubule organizing center.
1 Night terrors are characterized by frequent recurrent episodes of intense crying and fear during sleep, with difficulty arousing the child. Night terrors are frightening episodes that disrupt family life.  A small percentage of children experience night terrors.
The cause of night terrors. Night terrors can occur at any age, but small children seem to suffer from them most frequently. In fact, up to 15 percent of kids reportedly experience at least one night terror, says Dr. Markham.ight terrors can occur at any age, but small children seem to suffer from them most frequently. In fact, up to 15 percent of kids reportedly experience at least one night terror, says Dr. Markham.