What article or group of articles addesses the protection of rights?

Might you be referring not so much to specific articles within the US Constitution itself, but to the Bill of Rights, which is what we call the first 10 amendments to the Constitution?
1st amendment:  Freedom of speech, free exercise of religion (and no state-established religion)
2nd amendment:  Right to bear arms
3rd amendment:  Restricted quartering of soldiers in private homes
4th amendment:  Protects against unreasonable search and seizure
5th amendment:  Right to due process of law
6th amendment:  Rights of the accused when put on trial
7th amendment:  Right to a jury trial 
8th amendment:  Prohibits excessive bail fees and cruel & unusual punishments
9th amendment:  States that the rights listed in the constitution are not exhaustive list of all rights citizens have
10th amendment:  Separation of powers