Medical Definition of SCINTILLATING SCOTOMA. : a blind spot in the visual field that is bordered by shimmering or flashing light and that is often a premonitory symptom of migraine attack. a blind spot in the visual field that is bordered by shimmering or flashing light and that is often a premonitory symptom of migraine attack.
The centromeres of chromosomes attach to the spindle fibers during metaphase. The spindle fibers bring about the separation of sister chromosomes to the opposite poles.When s â¦ pindle fibers do not attach to the centromeres, the doubling of chromosomes leads to polyploidy in the cell.Answered.he centromeres of chromosomes attach to the spindle fibers during metaphase. The spindle fibers bring about the separation of sister chromosomes to the opposite poles.
The chrosomsomes have already duplicated but are still in the form of loosely packed chromatin fibers. PROPHASE: During the prophase the nucleoli in the nucleus disappear. The chromatin fibers become tightly ccoiled and condense into chromosomes. Chromosomes line up in pairs and are joined at the centromere. In the cytoplasm, the spindle fibers begin to form and are made of microtubules.