Does it occur naturally? Water: It is a chemical compound made by two molecules of hydrogen and one molecule of oxygen. It exists in all three phases of nature. It is the most important human need for the survivor on earth. Answer and Explanation:1 ...
Carbon dioxide is a naturally occurring gas that is essential for life but has harmful effects upon the environment if it is released into the atmosphere in high concentration. This is true both in direct and indirect ways. Direct emissions are those which are produced directly by the burning o...
At that time Mars would have been much warmer and wetter than it is today with an atmosphere composed mainly of carbon dioxide just like that of the earth at the time. Under these conditions it is highly probable that life may have arisen on Mars as well.But even if life did not arise...
DNA could be manipulated to give materials special properties—for example, the ability to absorb carbon dioxide from the air, reflect heat during the summer, or glow at night. “We’ve mapped the DNA genome of all of those things, so it is now actually possible we could grow building ...
Unlike plants, where electron transfer in photosynthesis provides the energy for carbon fixation, Nitrobacter uses energy from the oxidation of nitrite ions, NO2−, into nitrate ions, NO3−, to fulfill their energy needs.Nitrobacter fix carbon dioxide via the Calvin cycle for their carbon requir...
The actual concentration need not be large for a substance to be a pollutant; in fact the concentration tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects...
Adrenaline or as it's commonly known, epenephrine is a hormone naturally produced in the body. Epinephrine plays an important role in the fight or flight reponse in the body by increasing heart rate, blood flow and glucose levels. Answer and Explanation:1 ...
[单项选择题]What does this man mean [A] He will come to have supper very soon. [B] He has already come to have supper. [C] He is walking to come to have supper. 本题来源:2016年江西公共英语考试真题卷 查看最佳答案和解析
How does carbon dioxide enter the blood and how is it transported? How do hydroelectric power generation stations work? Explain Hess's law in simple terms. How does the metal reactivity series work? Describe how methane gas can be generated, and explain why it is considered to be a greenhous...
Why does precipitation occur at the windward side of a mountain? Why might large rivers generally have greater light attenuation coefficients than do large lakes? Why does the eye pupil dilate (i.e. widen) in dim light? Why does the greenhouse effect in the atmosphere occur?