Are exteroceptors and interoceptors.
Answer: option c - in the coding region of the Pitx1 gene
Explanation:
Note that there is LACK OF SPINE, not the presence of defective spine; so, an heritable mutation must have occurred in the coding region of pix1 gene of freshwater sticklebacks resulting in absolute LACK OF SPINE
The statement 'when paired with an immunosuppressant drug, saccharine (sugar) did not have immunosuppressant effects on rats' is FALSE. Saccharine is an artificial sweetener.
<h3>Immunosuppressant drugs and saccharine</h3>
Immunosuppressant drugs are a type of drug that exhibits a depressive effect o the immune system of the individual.
Immunosuppressant drugs include, for example, adalimumab, infliximab, calcineurin inhibitors, cyclosporine, etc.
Moreover, saccharin is an artificial sweetener that is 400 times as sweet as sucrose (sugar).
Learn more about immunosuppressant drugs here:
brainly.com/question/830058