Building your cell…
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What you have to be able to explain
In bright light the pupil gets smaller, so less light enters the eye and the retina is protected. In dim light the pupil gets wider, so more light enters and you can see.
Bright light: the circular muscles of the iris contract and the radial muscles relax, making the pupil smaller. Dim light: the radial muscles contract and the circular muscles relax, making the pupil wider.
The ciliary muscles contract, the suspensory ligaments slacken, the lens becomes fatter (more curved) and refracts light more strongly.
The ciliary muscles relax, the suspensory ligaments tighten, the lens is pulled thinner (less curved) and refracts light less strongly.