Nitrogen is not necessary <span />
The red liquid that circulates in the arteries and veins of humans and other vertebrate animals, carrying oxygen to and carbon dioxide from the tissues of the body.
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Answer:
Likewise, competition for food among deep-water fish that eat the same types of food will .
Explanation:
Natural selection will condemn all deep-sea fish to the same environment that conditions them, those that cannot develop gills will be exposed to extinction, this refers to the theory of the evolution of the fittest by Charles Darwin.