The lens in the human eye is held in place by the suspensory ligaments attached to the ciliary body. The function of other components are as follows:
The smooth muscles attached to the ciliary body helps to control the shape of the lens.
Smooth muscles of iris help in regulating the diameter of the pupil.
Pectinate ligament attached to the iris is involved in the drainage of aqueous humour because it contains spaces between the fibres.