How does the brain's energy consumption depend on mental activity?

Color blindness is a recessive trait. the gene for color blindness is on the x chromosome. the family tree below shows the trait of color blindness. the only unknown is the mother in the first generation

Determine if the following statement is true or false. if true, choose true. if false, choose the rewording that is true. according to the law of independent assortment, alleles for each gene are inherited together so that they always stay together. according to the law of independent assortment, offspring express a combination of their parents' traits. according to the law of independent assortment, alleles for a characteristic split during meiosis and combine during fertilization. true according to the law of independent assortment, alleles for each gene are inherited independently so that no two alleles stay together.

There are fewer than 100 naturally occurring elements in the universe, but there are millions of different unified substances. explain how this can be true.