The fossils that provide information on the formation of an oxygen-rich atmosphere are the stromatilites from the Precambrian era. These are layered and columnar fossils consisting mainly of cyanobacteria which were the original life form back then. These bacteria took in carbon dioxide and produced oxygen by photosynthesis as early as 2.5 billion years ago (the earth is about 4.5 billion yrs old).
Answer: first 2 statements ie. It is essential that our diet provides these amino acids.
There are 20 essential amino acids.
It is going to be B. the word Bio means the earth. every time you hear the word Bio, then think about the earth
Answer:
The correct answer will be option-annelids
Explanation:
Annelids in the phylum of animals which includes about 22000 extant species. The animals of this group possess segmented body and thus are called ringed worms.
Each segment of the body contains the same organs and are usually found in the aquatic environment in the hydrothermal vents and the tidal zones. Some species are found in the terrestrial environment.
Since the biologist found the animal from the deep ocean with a segmented body and soft skin therefore, the animal belongs to the annelids.
Thus, option-annelids is the correct answer.
