Free Fatty Acid Metabolism during Embryogenesis of Periplaneta americana (L)

Abstract

EXERGONIC reactions involving predominantly the catabolism of lipid materials¹, particularly triglycerides^2,3, provide the developing oviparous arthropod embryo with the energy necessary to sustain the intense metabolic activity occurring during its embryogenesis. The integral metabolism of these lipids should be closely reflected in the pattern of the free or unesterified fatty acids during this period, for these acids ultimately are the oxidizable form of the stored glycerides. It is established from analytical data^2,4 and measurements of the respiratory quotient (R.Q.)⁵ that free fatty acids are catabolized to provide respiratory energy in both invertebrate and vertebrate tissue. The metabolic pattern of these acids was investigated with the developing embryo of the American cockroach, Periplaneta americana (L), as the experimental material.