Frederick Griffith's work with two strains of the same bacteria, one harmful and the other harmless, showed that:
A. cells contain a transforming factor.
B. a DNA molecule is a double helix.
C. two alleles interact to produce a trait.
D. DNA carries a code for making proteins.

The cluster of developing cells from conception until birth is called an

What is any method of measuring the age of an object or event in years, such as using atomic half-life?

In guinea pigs, black fur (b) is dominant over white fur (b). cross a heterozygous (hybrid) black guinea pig with a homozygous (purebred) white guinea pig. complete a punnett square, identify the genotype(s), phenotype(s), and probability (% and fraction) that the offspring will be black and white?