Characteristics of Protostomes and Deuterostomes
In this article we will discuss about the development characteristics of protostomes and deuterostomes. Protostomes: Developmental Characteristics: 1. Pattern of embryonic cleavage: Spiral cleavage pattern; the spiral cleavage is masked at the 6th cleavages (64-cell stage), e.g., Sipuncula, Echiura, Annelida, Pogonophora, Mollusca and some groups of Arthropoda (e.g., Myriapoda, Crustacea and Insecta except Chelicerata). 2. Fate of embryonic blastomeres: Determinate [...]