The credit committee or duly appointed loan officer shall approve, in writing, every loan or advance made by the credit union, subject to any limitations that may be set from time to time by the board of directors. Every application for a loan shall be made in writing and shall state the purpose for which the loan is desired and the security offered. No loan shall be made unless the credit committee or loan officer is satisfied that it promises to benefit the borrower, nor unless it has been approved by the committee or duly appointed loan officer in accordance with applicable credit union bylaw provisions. The applicant for a loan may appeal the decision of the credit committee or loan officer to the board of directors. If written approval of the credit committee or loan officer is obtained, nothing contained in this section shall prevent a credit union from extending credit to a member in any manner in which it sees fit; provided that no extension of credit shall be made upon an unsecured revolving credit plan, line of credit, or letter of credit in which the credit authorization exceeds five thousand dollars ($5,000), unless the credit authorization is reviewed at least annually by the credit committee, if one exists, or by the board of directors.