Photoautotrophs Chemoautotrophs Cyanobacteria were the first organisms that released oxygen as a by-product of photosynthesis User: Gymnosperms and angiosperms that were more adapted to land were seed-bearing and able to reproduce using _____.
pollen
cones
flowers
seeds User: Scientists believe cyanobacteria chemoautotrophs photoautotrophs were the first types of cells able to make their own food.