Please help this is due tomorrow.

Some heterozygous alleles create variations in expression so that there is not a clear dominant or recessive allele. question 1 options: true false

Which of the following statements is true? 1. the mantle of the earth is made of solid nickel and iron. 2. the crust of the earth is made of solid nickel and iron. 3. the inner core is made of solid nickel and iron.

The first signs of cellular differentiation occur in the blastocyst. why is cellular differentiation important for the development of a fully formed human infant?