The production of C¹⁴O₂ metabolized from glucose labeled in
specific carbon atoms by homogenates of chick embryonic and adult
heart was compared by the radiorespirometric technique. Homogenates
of early (two to five days of incubation) embryo hearts were
found to utilize the phosphogluconate pathway of glucose catabolism
to a greater...
Isocitrate-NADP oxidoreductase activity in mitochondrial and
soluble fractions was determined for hearts, livers and brains of
chick embryos at various stages of development. One-half to two-thirds
of the activity in brain and liver homogenates is located in the
soluble fraction. Supernatant activity increases in these organs to a
Levels of activity of glucose-6-phosphate- , 6-phosphogluconate- , and isocitric- dehydrogenase were measured in the
soluble and particulate fractions of heart, brain and liver at
several ages throughout the development of the chick embryo.
Compared to isocitric dehydrogenase, levels of glucosesphosphate-
, and 6-phosphogluconate- dehydrogenase are generally
low. This suggests...
Carnitine, acetylcarnitine, and long-chain acylcarnitine concentrations
were determined for heart, brain, and liver of chick
embryos during various stages of development. The total carnitine
concentration was approximately the same in all three organs and
showed only small variations during development. Acetylcarnitine
was not detected in any organ until the seventeenth...
Patterns of nest attendance behavior by breeding birds represent a parent-offspring trade-off in which adults balance self-maintenance with parental care decisions.
Incubation, in particular, is of interest because adults must provide an environment
suitable for embryonic development through nest-building and contact-incubation.
We evaluated how adult incubation constancy and nest visitation...