is the process by which the. chemical energy. of food molecules is released and partially captured in the form of ATP. Cellular respiration is the general term which describes all metabolic reactions involved in the formation of usable energy from the breakdown of nutrients.
More pi history: European mathematicians in the early modern period developed new arithmetical formulae to approximate the value of pi, such as that of James Gregory (1638-1675), which was taken up by Leibniz: /4 = 1 - 1/3 + 1/5 - 1/7 + . . . . . . . . . . .
1 The first 10 and 50 digits of Pi: 3.14159265 35897932384626433832795028841971693993751.  More digits: Scroll down to see the first 10,000 digits of Pi at the bottom of this page, or grab even more using the links below.