251 million years ago, the Permian extinction occurred. It is the widest and most massive extinction that wiped out 85-90% of marine species and 70% of land vertebrates at that time. There were recorded low oxygen levels in deep and shallow oceans, extreme shift in the carbon cycle, massive eruption of a basal salt volcano in Siberia and the consecutive global warming that occurred evidently ended early prehistoric life.
<h2>Answer:</h2>
The statement that most directly explain this concept is "nitrifying bacteria that convert ammonia into nitrites and nitrates are found in the soil".
<h2>Explanation:</h2>
Bacteria living in the soil in root nodules of various plants are directly involved in the nitrogen cycle. The nitrifying bacteria "<em>Nitrobacters" </em>and "<em>Nitrosomonas"</em> can fix atmospheric nitrogen and can convert it into nitrates and nitrites. As plants can not directly fix that atmospheric nitrogen so these <em>Nitrobacters</em> and <em>Nitrosomonas </em>who lives in symbiotic relation in their root nodules do this nitrogen fixation for them. So these bacteria provide them nitrates and nitrates that plants can directly uptake and can use in their essential metabolic cycles. In this way, Geosphere plays a critical role in nitrogen fixation.
Nitrogen gas is most commonly found in which earths sphere?a. Biosphere
b. Exosphere
c. Atmosphere
d. Hydrosphere
Air moves into the lungs when the air pressure in the lungs is lower than the air pressure outside of the lungs. This occurs when the muscels of the diaphragm contract.
You can see this by breathing in and out deeply. When you breath in you can feel your chest being pushed up and out by your diaphragm. The reason the pressure in the chest is lower is that when you breathe in you are increasing the volume of your chest. As there is the same amount of air in your chest the pressure decreases.
This is the best answer Biochemical evidence <span>It's basically the same thing as molecular evidence, because biochemistry deals with biological molecules such as DNA. </span>
<span>We could also do this by process of elimination. All of the other answers are MUCH worse than biochemical evidence.</span>
