Formation of germ cells in Drosophila and many other embryos is dependent on their position in the embryo and their exposure to localized cytoplasmic determinants. Nuclei exposed to cytoplasm in the posterior end of Drosophila eggs (the pole plasm) form cells that develop into germ cells under the direction of maternally derived components. R. Amikura et al. [(2001). Proc. Nat. Acad. Sci. (USA) 98:9133–9138] consistently found mitochondria-type ribosomes outside mitochondria in the germ plasma of Drosophila embryos and postulated that they are intimately related to germ-cell specification. If you were studying this phenomenon, what would you want to know about the activity of these ribosomes?