Describe the changes that take place in the iris when moving into a dark room.

The iris controls the diameter of the pupil to accommodate for the level of light that needs to enter the eye. When an individual moves into a dark room, the pupil must dilate to allow more light to enter the eye. Radial muscles in the iris contract, enabling the pupil to dilate and therefore, the eye can still see in darkness.

PT
Answered by Pauline T. Biology tutor

17902 Views

See similar Biology GCSE tutors

Related Biology GCSE answers

All answers ▸

What are the main stages of the cardiac cycle?


Outline the lock and key mechanism of enzyme-controlled reactions


Describe how water moves from the roots to the leaves in plants


How is it possible for a metal to transfer thermal energy?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning