Answer :There was enough oxygen in the atmosphere to support a major burst of life on Earth
Explanation:
The Great Oxygen Event marks the time, approximately 2.5 billion years ago, when there was enough oxygen in the atmosphere to support a major burst of life on Earth
For the first half of the Earht's history, there was no oxygen in the atmosphere. It was inhabited only by single-celled organisms.Of those simple life forms, the cyanobacteria may have. evolved a way to take energy from sunlight, and used it to make sugars out of water and carbon dioxide. They used the same chemical process we know as photosynthesis. This released vast quantities of oxygen into the atmosphere and triggered the evolution of complex life.
1. Stomach, Breaks down food with acid located in the stomach
2.Mouth, Chews and Grinds food down. Allows the breakdown of enzymes
3.Kidneys, Take out any unhealthy/unneeded substances in the food.
4. Large Intestine, The formation of feces.
Fossil fuel power burn carbon fuels such a coil,oil or gas to generate that drives large turbines that produces electricity by burning carbon fuel they produce large amount carbon dioxide.
Answer:
Its D, The cell membrane(also known a the plasma membrane) has a job in which it has to allow passage in and out of the cell. Therefore it can prevent harmful substances from entering the cell. Think of it as security, either allowing you access or denying you depending on if you're a threat
