Transitional elements in life

Among the transition elements, vanadium , chromium , manganese , iron , cobalt , nickel , copper , zinc , and molybdenum are trace elements necessary for life, and most of them are the fourth period elements (Table 16-2)
.

Table 16-2 The content of essential transition elements in human body

Iron is the transition element with the highest content in the human body.
The content in the human body is 4.

Zinc is the active center of many enzymes and participates in various metabolic processes
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For example, the synthesis and degradation of carbohydrates, lipids, proteins and nucleic acids; zinc is related to bone and intellectual development, and zinc deficiency may cause dwarfism; zinc coordination compounds play a buffering role in the pH control mechanism in the body; carbonic anhydride Enzymes can catalyze the reaction of CO ₂ and H ₂ O, so that CO ₂ in the body can be discharged from the body in time

The content of cobalt in the human body is only 1 to 2 mg, concentrated in the liver, mainly in the form of vitamin B ₁₂ and its derivatives, and has the function of treating anemia
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Cobalt plays a role in organisms in coenzymes, promotes the maturation of red blood cells, participates in protein synthesis, hydrogen and methyl transfer, and participates in redox reactions

Copper contains 100-150mg in the human body, and more than a dozen enzymes have been found to contain copper
.
Iron absorption and utilization process requires plasma ceruloplasmin involved

Molybdenum participates in metabolism, can prevent the synthesis of nitrous acid and has anti-cancer effects
.
The active center of nitrogenase is Mo-Fe protein or Mo-Fe-S protein, which plays an extremely important role in the process of biological nitrogen fixation

Manganese is an activator of certain enzymes and a cofactor for respiratory enzymes in mitochondria
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Nickel exists in the serum of humans and mammals
.
Studies on animals have shown that a lack of nickel will affect the absorption of iron and reduce the amount of hemoglobin and the number of red blood cells

Chromium is a cofactor of insulin, and insulin has the function of promoting sugar metabolism
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Chromium inhibits the synthesis of cholesterol and fatty acids, affects the utilization of amino acids, and has the effect of preventing atherogenesis

Vanadium can promote tooth mineralization, prevent dental caries, and reduce the content of cholesterol in serum