Which statement best describes the relationship between an allele and a gene? A
An allele is a variation of a gene that can be expressed as a phenotype.

B
An allele is a segment of a DNA molecule that controls replication of a gene.

C
An allele is the primary protein made by a gene found in a developing embryo.

D
An allele is the part of a gene that attaches to messenger RNA molecules.

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.

What is the difference between sex-linked traits and autosomal traits in humans? a. sex-linked traits can only be passed from fathers to sons, while autosomal traits can be passed on from both parents to offspring of any sex. b. sex-linked traits are passed on through the x and y chromosomes, while autosomal traits are passed on through the other 22 chromosomes. c. sex-linked traits only affect females, while autosomal traits affect both males and females. d. sex-linked traits refer to genes that are on the x and y chromosomes, while autosomal traits refer to genes on all 23 chromosomes.

Which enzymes break down carbohydrates?