Discipline is action or inaction that is regulated to be in accordance with a particular system of governance. Discipline is commonly applied to regulating human and animal behavior to its society or environment it belongs, while self discipline is the ability to control one's feelings and overcome one's weaknesses; the ability to pursue what one thinks is right despite temptations to abandon it.
Discipline is a moral obligation among many groups of people. Disciplined behavior is required by some laws and other legal obligations.
Commercial entities can also put in place strict disciplinary requirements for the length of the commercial agreement.
Airlines enforce strict disciplinary and conduct rules upon flight passengers, Etcetera.
The nucleus is a membrane-enclosed organelle found in most eukaryotic cells. The nucleus is the largest organelle in the cell and contains most of the cell's genetic information (mitochondria also contain DNA, called mitochondrial DNA, but it makes up just a small percentage of the cell’s overall DNA content)