SCIENCE--Which of the following was one of the earliest events allowing for the production of oxygen in the atmosphere? Select o
ne: a. Plants photosynthesizing carbon dioxide. b. Bacteria photosynthesizing dissolved carbon dioxide in oceans c. Volcanoes releasing oxygen into the atmosphere
b. Bacteria photosynthesizing dissolved carbon dioxide in oceans
Explanation:
The levels of oxygen that we know nowadays in the atmosphere have not been like this in the more distant past. In order for the oxygen to start building up and change the composition of the atmosphere, something needed to happen, and that something was the cyanobaceteria. The cyanobacteria was able to perform photosynthesis, so it started to use the dissolved carbon for it, while in meantime it was releasing oxygen in the atmosphere. As the cynaobacteria was growing in numbers, over the course of millions of years, it managed to propel enough oxygen in the atmosphere so that the other organism can start developing, thus changing the world forever.
"Domesticated animals are animals that have been selectively bred and genetically adapted over generations to live alongside humans." (Nation Geographic's Definition of Domesticated Animals)
The true statement is - Sympatric speciation only occurs in areas where there is local variation in environmental resources
Explanation:
Sympatric speciation means the evolution of new species from an ancestor species which are occupying in the same area and no geographical barrier takes place.
Overlapping of ranges takes place to the organism and old and new species are living i the same geographical region.
A dam diving a fish population could lead to allopatric speciation where geographical barrier causes formation of new species which are completely different from their ancestor species.
