answersLogoWhite

0


Best Answer

It depends on how much light your eyes receive, in dark places or when you close your eyes your pupils dilate (mydriasis) to increase the ammount of light they can take in, conversely, when looking at an intense light the pupils contract (miosis) to decrease the ammount of light. This is called the photomotor reflex and involves the sympathic (mydriasis) and parasympathic (miosis) nervous pathways.

User Avatar

Wiki User

12y ago
This answer is:
User Avatar
More answers
User Avatar

Wiki User

15y ago

This happens because the muscles in the iris (the coloured part) close in to make the pupil smaller when there is to much light to protect the little cells in your eyes. It also happens vice versa to make the pupil bigger when there is little amount of light.

This answer is:
User Avatar

User Avatar

Wiki User

16y ago

As it gets darker, pupils get bigger. (They also get bigger when viewing something the person likes)

This answer is:
User Avatar

User Avatar

Wiki User

13y ago

Ok your eyes open in the dark to let more light in. When it is very bright your pupel gets smaller to block light.

This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: How does the size of the iris and pupil change?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Related questions

Which part of the eyes control size of the pupil?

the part of the eye that controls the pupil is the iris


Is it possible for your pupil to grow bigger than your iris?

No. The pupil can only open to the size of the iris.


How does the iris control the size of the pupil?

the iris


Where is the iris located?

The iris is the layer that surrounds the pupil and controls the size and diameter of the pupil. It also controls the amount of light that reaches the pupil.


What is the opening that is controlled by the muscles of the iris?

The opening that is controlled by the muscles of the iris is called the pupil. The iris is responsible for adjusting the size of the pupil in response to different lighting conditions.


What are the rings of muscle around the pupil gives the eyes color?

it is known as Iris. contraction or relaxation of iris alters the size of pupil.


Colored part of the eye that contracts or relaxes in response to light?

The Iris contains the muscles that control Pupil size.


What contains muscle that controls the size of the pupil?

iris


What is the colored ring of muscle that controls the size of the pupil is called?

The Iris.


The colored ring of muscles that controls the size of the pupil is called?

iris


What acts as a reflexively activated diaphragm to vary pupil size?

The Iris.


How many pupil are in an eye?

There is one pupil in each eye. The pupil is the opening in the center of the iris that allows light to enter the eye. Its size can change depending on the lighting conditions to regulate the amount of light entering the eye.