(a) The certificate of incorporation or a by-law adopted by the members may contain provisions specifying either or both of the following:

(1) That the proportion of directors that shall constitute a quorum for the transaction of business or of any specified item of business shall be greater than the proportion prescribed by this chapter in the absence of such provision.

(2) That the proportion of votes of directors that shall be necessary for the transaction of business or of any specified item of business shall be greater than the proportion prescribed by this chapter in the absence of such provision.

(b) An amendment by the members of the certificate of incorporation or of the by-laws which adds a provision permitted by this section or which changes or strikes out such a provision, shall be authorized by vote of two-thirds of the members entitled to vote or of such greater proportion as may be provided specifically in the certificate of incorporation or the by-law for adding, changing or striking out a provision permitted by this section.

(c) If there are no members, an amendment by the board of directors of the certificate of incorporation or the by-law which adds a provision permitted by this section or which changes or strikes out such a provision, shall be authorized at a meeting by vote of two-thirds of the entire board, or of such greater proportion as may be provided specifically in the certificate of incorporation or the by-law for adding, changing or striking out a provision permitted by this section.