1 Secretion of erythropoietin, which regulates red blood cell production in the bone marrow. 2  Secretion of renin, which is a key part of the reninâangiotensinâaldosterone system. 3  Secretion of the active form of vitamin D (calcitriol) and prostaglandins.
A: A charter school is a public school that is organized and operated according to the terms of the. charter, or contract. A charter school cannot have admissions criteria or charge tuition. A private school is not subject to state school laws, local board of education policies, or State Board of Education rules.
Charter schools in the United States. In 2003 Granada Hills Charter High School became the largest charter school in the United States. Charter schools in the United States offer primary or secondary education without charge to pupils who take state-mandated exams.