Alternate director - requirement?

As per Section 149 of the Companies Act, 2013, Minimum number of directors for private limited company is 2 and for public limited company is 3.

As per section 173 of the Companies Act, 2013 every company shall  hold a minimum number of 4 meetings of its Board of Directors every year in such a manner that not more than 120 days shall intervene between two consecutive meetings of the Board:

As per section 167(1)(b) , director absent himself from the entire board meeting held during a period of 12 months with or without obtaining leave of absence, his office as director shall vacate.