(a) Sick leave for employees of the legislative branch, including employees of the lieutenant governor, is determined as follows:
(1) for employees of either house of the legislature, a member of the legislature, or the lieutenant governor, by the presiding officer of the appropriate house of the legislature; and
(2) for employees of a legislative agency, by the administrative head of the agency.
(b) An employee of an institution of higher education as defined by § 61.003, Education Code, is eligible to accrue or take paid sick leave under this subchapter only if the employee:
(1) is employed to work at least 20 hours per week for a period of at least four and one-half months; and
(2) is not employed in a position for which the employee is required to be a student as a condition of the employment.