It’s very confusing sorry for that
That is where the fibers of the optic nerve exit the eye extending into the brain. there are no rods and cones there as a result.
Answer: they are all prokaryotes
Explanation: because they all lack a nucleus to retain their DNA
The generalization that all organisms are composed of cells was established through multiple observations in various kinds of animals and plants. A controlled experiment of finding cells in all the kinds of living organisms is not possible or is infeasible as it will require prior knowledge of all the kinds of organisms inhabiting Earth and the effort to catch and bring them in the controlled environment of the lab for testing.