[Solved] The embryo develops from the embryonic disk, which is A)the inner layer of the blastocyst. B)an inner organ of the fetus. C)the unfertilized ovum. D)a type of teratogen. Systemic Anatomy: The study of the body's systems, looking at how various organs and structures function together. Molecular Biology: A branch of biology that focuses on the structure and function of the molecules that make up cells, particularly DNA, RNA, and proteins. Microbiology: The branch of science concerned with microorganisms and their effects on other living organisms. Surface Anatomy: The study of the external features of the body and their relationship to deeper structures, as visible to the naked eye without dissection.