A conditioned stimulus when paired with a bell. When the bell was rang food was presented. So upon hearing the bell the dog would salivate because he knew simply put food would then follow. This became known as classical conditioning.
Nucleic acids,proteins,carbohydrates and lipids
I believe it is A. Please forgive me if I am wrong.
Answer:all of the above is the correct answer
Explanation: trust me
Nucleus is the correct choice, bacteria cells lack a Nucleus
