The greater amount of eumelanin in darker skin protects folate from being broken down by UV radiation and thus increases fitness among populations in high-intensity UV areas. ... However, it does not explain why there is variation in human skin color.
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Carolus Linnaeus is the father of taxonomy, which is the system of classifying and naming organisms. One of his contributions was the development of a hierarchical system of classification of nature. Today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.
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The three examples of cycles of inorganic nutrients are Nitrogen, carbon and sulphur cycle.
Nitrogen is required to make amino acids and DNA in organisms. Carbon is the main component of glucose through which organism make energy, about 18 per-cent of the human body comprises carbon. Sulphur is an important constituent of some proteins, amino acids and enzyme cofactors.
Explanation:
The biogeochemical cycles like the nitrogen cycle are responsible for converting nitrogen into many chemical forms as nitrates, nitrites, ammonia. This process involves degrade decomposing animal and plant matter and naturally cleaning the environment also nitrites and nitrates become biofertilizers. The plants take nitrogen through their roots and in turn primary consumer in food chain ie. organisms consume the plant and eventually releases nitrogen as a waste material, dead and decaying body to the soil and cycle goes on.
In the carbon cycle the carbon is exchanged from the atmosphere to the organisms and then again to the environment. Plants perform photosynthesis by using carbon dioxide, primary consumer eats it and gets nutrition to perform cellular respiration, in turn, gets energy which gets dissipated and stored as biomass eventually in the course consumer die and replenish the soil with carbon. The Carbon emitted will keep cycling through air, water and soil.
The sulphur cycle involves the movement of sulphur between rocks, water and living beings and plants. Plants ( producers) absorb sulphur dissolved in water and animal consume these plants to replenish their sulphur requirement. And when organism die, sulphur enter the cycle again.
There will be a transfer of these inorganic nutrients to the trophic level in food chain.
