there is no need to find a mate
Iodine is a non-metallic, dark-gray/purple-black, lustrous, solid element.
I'm not sure how exactly you wanted this question to be answered. You're either talking about the symmetry where animals would have two legs or two arms for example and thus producing a pair of each muscle on both sides of the body, or you're refering to the development of agonistic and antaonistic muscles where each of them served a different purpose; either extending or contracting.
During the process of biological magnification , the concentration of pollutants, such as DDT or mercury, is multiplied as it passes up a food chain.
Answer:
La vida en la Tierra. Los estudios de los fósiles de rocas antiguas nos revelan que la vida probablemente comenzó hace unos 4 billones de años, cuando la Tierra era muy joven. Nadie sabe cómo comenzó la vida en nuestro planeta. La mayoría de los científicos piensa que se originó en el agua líquida
Explanation:
