Abstract
Glycogenesis and glucose uptake of Hymenolepis diminuta and H. citelli are stimulated by 5% carbon dioxide but less stimulated by 20% carbon dioxide. The stimulatory effect occurs aerobically and anaerobically with H. diminuta. Oxygen (air) has no significant effect on glycogenesis, glucose uptake, or incorporation of glucose-Cl4 into glycogen in H. diminuta, although there was an apparent increase in C14O2 fixation in glycogen under aerobic conditions. The pattern of glycogenesis with time was sigmoid, although glucose uptake in the same experiments was almost linear. The addition of dicarboxylic acids or dicarboxylic amino acids did not serve as a replacement for carbon dioxide in stimulating glycogenesis or glucose uptake. Malate produced no significant effect on the incorporation of glucose-C14 into glycogen. The rate of glucose uptake was dependent on concentration up to about 10 mM. Galactose is absorbed at a high rate but does not serve as a substrate for net glycogenesis.