In the open ocean, tiny organisms called (animal plankton / bacteria / decomposers / phytoplankton) perform photosynthesis. They are the primary producers in many (ecological pyramids / food chains / food webs trophic levels) that overlap to form a(n) (ecological pyramid / food chain / food web / trophic level).

Pls me i need this ! each cell has genes activated depending on it's job and what kind of cell it is. it is the presence of that causes the repressor protein to fall off and unblock the gene on the lac operon. if a gene is turned on then it is being an additional circular chromosome found in some bacteria that is used in genetic engineering.