With the approval of the Governor, the Secretary shall appoint a Deputy Secretary. The Deputy Secretary: serves at the pleasure of the Secretary; is entitled to the salary provided in the State budget; and has the duties provided by law or delegated by the Secretary. Each assistant secretary and professional consultant is in the executive service, management service, or is a special appointment in the State personnel management system and is appointed by and serves at the pleasure of the Secretary. Except as provided in this section or otherwise by law, the Secretary shall appoint and remove all other staff in accordance with the provisions of the State Personnel and Pensions Article. The appointment of or removal of staff of any unit in the Department is subject to the approval of the Secretary.