Limiting factors are what controls the population of an ecosystem. It also limits the kind of organisms that inhabit it. Limiting factors can be abiotic or biotic. Abiotic factors are the nonliving factors that affect the living ones. From the given options above, the only biotic limiting factor is vegetation. The correct answer would be option B.
*The key function of each of the two photosystems is to absorb light and convert the energy of the absorbed light into redox energy, which drives electron transport.
In PS II (the first photosystem in the sequence), P680 is oxidized (which in turn oxidizes water), and the PS II primary electron acceptor is reduced (which in turn reduces the electron transport chain between the photosystems).
In PS I, the PS I primary electron acceptor is reduced (which in turn reduces other compounds that ultimately reduce NADP+ to NADPH), and P700 is oxidized (which in turn oxidizes the electron transport chain between the photosystems).
Bauxite does not have a specific composition. it's a mixture of hydrous aluminum oxides, aluminum hydroxides, clay materials, and insoluble materials such as, quartz, hematite, magnetite, siderite, and goethite
<span>The elements that are found in a high proportion in Earth's crust are oxygen, aluminium, iron, calcium, potassium, sodium, and magnesium. But for your Option, I think it is B) Oxygen and Silicon. This is because Oxygen makes 46.6% while Silicon makes 27.7% of the Earth crust.</span>