Answer: net primary productivity is the amount of energy lost through respiration by producers SUBTRACTED From the gross primary productivity of an ecosystem
The answer is iron. Research has shown an increase in serum iron concentreation in athletes and a concomitant decrease in magnesium ions. The increase in iron concentration is thought to be attributed to tissue injury from the strenuous physical activity. The decrease in magnesium is due to demand by the skeletal muscles.
The energy the sun produces is nuclear more specificly nuclear fusion which emits a lot of light
