Copper deficiency is a rare disease that leads to hematological disorders. It is an essential trace element. It is an essential part of some enzymes (c0-factor) that plays role in cellular respiration. Copper is also an anti-oxidant that scavenges free radicals. In case of cellular respiration copper is responsible for electron transfer of oxygen.
I think Oxygen is the best answer.
Astronomy can best be described as a "<span>a. study of objects beyond earths atmosphere", although the subject of astronomy can be much more complicated. </span>
Spermatogenesis produces<span> four </span>gametes<span>, while </span>oogenesis produces one with two to three polar bodies left over. because oocytes contain not only genetic material but also mitochondria.
<span>Meteorology is BEST defined as the study of weather and climate.</span>
