Dark black part in middle of eye??

Question

Why does it change sizes. I have blue eyes, and i noticed the black part in my mid-eye was very very small. Sometimes it's big. Why does it change???

Answer 1

You are referring to the pupil.The pupil is a hole, the Iris, (the colored area around the pupil) opens and closes to compensate for brighter or dimmer light.

Answer 2

the pupil dilates and gets bigger to let more light in when its dark so you can see. Also when you want to see more of something. It gets smaller when you want to less light in when its too bright

Answer 3

yup the muscles in your eye contract to make it smaller, so that it doesn't suffer damage from the light. When it's pitch black around you, they get very large.