Thus, we hypothesize that exposure to PVC leachate will disrupt the microbiome community, alter gene expression in cell signaling and transport pathways involved in early embryonic development (Tarrant 2005), and impair survival and development. This study provides insight into how plastic derived chemicals pollution may affect coral early life stages, a critical but under-explored phase of reef resilience and recovery.
to me this should be the final paragraph of the Introduction. Go ahead and enumerate hypothesis and consider the order you state them and follow that same pattern throughout the paper.