A(n) is a chamber that isolates the subject from the external environment.

Answer;

A skinner chamber

A skinner chamber is a chamber that isolates the subject from the external environment.

Explanation;A skinner chamber or skinner box an enclosed chamber which contains a bar or key that an animal can press or manipulate in order to obtain food or water as a type of reinforcement.This box was used by Skinner in his experiments concerning Operant conditioning. From the experiments that he conducted he realized that the important part of any operant conditioning id recognizing the operant behavior and the outcome resulted in that particular environment.

Biochemistry, it deals with the chemical constitution, the breakdown and the synthesis of plant and animal products.