Answer:
Biotic means living so all biotic factors rely on each other to survive
Answer:
Single loop
Double loop
Explanation:
Circulatory system in the body helps in the transport of oxygen, nutrients and other important substances in the body.
Single loop circulatory systems involves blood passing through the heart only once on each circuit around the whole of the blood circulation system of the animal.
Double loop means there are two loops in our body in which blood circulates. One is oxygenated which means oxygen rich and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.
I think it’s b sorry if i’m wrong
Answer:
2.7 billion
Explanation:
This period is referred to as the Great Oxygenation Event. This period saw the evolution of photosynthetic organisms (cyanobacteria) that utilized carbon dioxide (that dominated the atmosphere then) and sunlight to manufacture their energy molecules-glucose. Photosynthesis produces oxygen as a byproduct that is evolved into the atmosphere. As these photosynthetic organisms proliferated on earth, the atmosphere composition changed to become partly dominated by oxygen (which is an oxidaton agent) with less and less carbon dioxide.
Its not really thats but in some case i guss it can be but if we did not have nuculer eneger the planet would be safer