What is a carbohydrate? O a macromolecule used for long-term energy storage
O a macromolecule that is used to build muscles
O a macromolecule used to create genetic material
O a macromolecule that produces quick energy

By 2 weeks after fertilization the morula has implanted into the uterine lining and transforms into a(n) . this time is when the , or the organ that will provide nourishment to the fetus by exchanging nutrients and waste products, begins to develop.