Cyanobacteria which is a type of algae. It conducts photosynthesis and without it there may not have been life today because they didn't need oxygen to survive and in order to have oxygen there had to have been some form of life...
Protist are eukaryotic organisms that cannot be classified as a plant animal fungus. They are mostly unicellular, but some like algae, are multicellular. Kelp, or “seaweed” is a large multicellular protist that provides food, shelter, and oxygen for numerous underwater ecosystems.
Answer:
Newton's law of gravitation, statement that any particle of matter in the universe attracts any other with a force varying directly as the product of the masses and inversely as the square of the distance between them
Plants have both a cell wall and a cell membrane.
The answer is early prophase. Hope this helps