title: Microspectrophotometry of nuclear DNA during the early development of a sea urchin, a sand dollar, and their interordinal hybrids.
mesh_terms: D000367:Age Factors; D000818:Animals; D002467:Cell Nucleus / Q000032:analysis* / Q000378:metabolism; D004247:DNA / Q000032:analysis* / Q000096:biosynthesis; D004447:Echinodermata / Q000196:embryology / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D006824:Hybridization, Genetic; D008722:Methods; D012617:Sea Urchins / Q000196:embryology / Q000378:metabolism; D013053:Spectrophotometry
chemical_list: D004247:DNA