What is the function of protons, neutrons, and electrons?

Explanation:

Protons help bind the nucleus together. They also attract the negatively charged electrons, and keep them in orbit around the nucleus.

Electrons create a negative charge that balances the positive charge of the protons in the atomic nucleus.

Netrons are responsible for combining with protons in the nucleus together to be held by the strong force.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.