Reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller
Else clues• Constriction of pupils
• Constriction of the pupil
• Excessive contraction of the pupil
• Reproductive cell division
• (genetics) cell division that produces reproductive cells in sexually reproducing organisms
• The nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants)