Choose between the two options to answer the question specified in the brackets for the following: Example: Corolla or Calyx (Which is the outer whorl?) Answer: Calyx
Sclerotic layer or choroid layer (Which one forms the Iris?)
Topic: Choroid forms the iris
Answer
The CHOROID layer.
The CHOROID continues forward at the front of the eye as the CILIARY BODY and then as the IRIS.
The SCLERA continues forward as the transparent CORNEA — which is what Question 1(a)(iv) of this same paper asks. The two questions test the same idea from opposite ends.
THE PATTERN worth holding once and for all:
SCLERA → becomes the CORNEA
CHOROID → becomes the CILIARY BODY and the IRIS
RETINA → remains the retina
It also explains the iris being PIGMENTED: the choroid is a darkly pigmented layer, and the iris inherits that pigment — which is what gives eyes their colour.