What is a major source of carbon in the marine ecosystem? a- calcium carbonate released by marine animals. b-carbon dioxide released during photosynthesis of marine plants. c-carbon dioxide released from the fossils of marine organisms

Which of the following can occur to two segments of a population if they are geographically isolated 1.) they can only share some types of genes 2.)both groups most likely become extinct 3.)they find a way to come back together 4.)eventually they become separate species