Mario sets up an experiment to determine the source of the oxygen gas produced by photosynthesis. To determine this, he uses an isotope of oxygen called O-18. He labels the O-18 oxygen so he can follow its path through photosynthesis. Plant A is given carbon dioxide that contains the O-18 isotope. Plant B is given water that contains the O-18 isotope. When he examines the oxygen from both plants, only plant B produced O-18 oxygen. This indicates that the source of oxygen is water. The photosynthesis involves the transfer of electrons between the photosystem I and II. The water gets split into oxygen, hydrogen ions and electrons in the photosystem I. The electrons move to the photosystem II where the carbon fixation into sugars takes place. The plant A will have O-18 isotope in its synthesised sugar molecule, which gets stored inside it.
Answer:
D
Explanation:
Water and air circulate around the world in water currents and wind systems (like prevailing winds) respectively, hence distribute energy and whatever else they are carrying across the globe. This is why polluting the oceans in the equatorial region will have indirect consequences for marine life in the poles.
Pollution of air through emission of greenhouse gases in one part of the globe will contribute to global warming across the world because these emissions will be carried around by prevailing winds and diffuse across the atmosphere.
Global warming also causes climate change that subsequently causes the displacement or migration of organisms when this change in climate is unfavorable
<span>Bacteria is needed to convert nitrogen gas/ammonia into nitrates for "enhancing" the growth of plants.</span>
