What is the difference relative and absolute dating?

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

What is the function of the somatic nervous system? connects the brain and the spinal cord to the rest of the body carry signals to the muscles and glands includes all nerves controlling the muscular system and external sensory receptors controls internal organs like the heart and bladder

Reactants undergo chemical reaction to form products. this chemical equation represents one such reaction. the coefficient for one of the reactants or products is incorrect. which part of the chemical equation is incorrect?