1) There are three layers of neurons in the retina. The axons of which of these neuron layers form the optic nerves? A) cone cells B) ganglion cells C) bipolar cells D) rod cells B) ganglion cells 2) Ordinarily, it is not possible to transplant tissues from one person to another, yet corneas can be transplanted without tissue rejection. This is because the cornea ________. A) does not contain connective tissue B) has no blood supply C) is not a living tissue D) has no nerve supply B) has no blood supply 3) Which of the following is not a possible cause of conduction deafness? A) middle ear infection B) impacted cerumen C) cochlear nerve degeneration D) otosclero C) cochlear nerve degeneration 4) Which of the following is true about gustatory receptors? A) In order for a chemical to be sensed, it must be hydrophobic. B) Complete adaptation occurs in about one to five minutes.