A mother who is blood type O can only pass an O allele to her son or daughter. A father who is blood type AB could pass either an A or a B allele to his son or daughter. This couple could have children of either blood type A (O from mother and A from father) or blood type B (O from mother and B from father).
At night, humans can use flashlights to spot animals that possess tapetum lucida by causing a phenomenon called eye shine.. Eye shine is the iridescent glow observed in animals when light is shone into their eyes, which floods the eye with light that is then reflected by the tapetum lucidum.
Quick Answer. The primary function of the human pupil is to regulate the amount of light that enters the eye. When the pupil is smaller, less light enters the eye in bright environments. The pupil gets larger as light levels decrease to let more light into the eye. Doctors examine the pupil to ascertain one's neurological function.