Which of the following is the main evidence of life in the early universe? a) plant remains. b) rock layering. c) dinosaur fossils. d) cyanobacteria

The correct answer is D. Cyanobacteria.

Explanation

Cyanobacteria are a group of bacteria that has the particular capacity of oxygenic photosynthesis, that is, the cyanobacteria produce oxygen using water. This contributed to the accumulation of oxygen in the atmosphere close to two thousand and seven hundred million years ago. This contribution caused the improvement of the biosphere in the Earth with the help from the oxygen produced by Cyanobacteria. Additionally, cyanobacteria are evidence of early forms of life in the universe considering these are one of the oldest organisms in Earth that lead to more complex life due to the oxygen they provided to the atmosphere. So, the correct answer is D. Cyanobacteria

organisms that are both used in toothpaste as well as cause malaria are protista and monera.

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.