The chemistry leading to life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10â17 million years old. Though life is confirmed only on the Earth, many think that extraterrestrial life is not only plausible, but probable or inevitable.he chemistry leading to life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10â17 million years old. Though life is confirmed only on the Earth, many think that extraterrestrial life is not only plausible, but probable or inevitable.
Anatomy is the field of science concerned with the study of the physical structures of an organisms. It's divided into several branches, including histology, embryology, gross anatomy, zootomy, phytotomy, human anatomy, and comparative anatomy.
Gross anatomy Gross anatomy is the study of structures which can be seenwith the unaided eye (the macroscopic structure of tissuesand organs). Histological anatomy Histological anatomy is the study of the structure of tis-sues. Histology is the study of the structure, as seen micro-scopically, and function of tissues. Microscopic anatomy Microscopic anatomy is the study of structures with theaid of a microscope. Microscopic anatomy includes thestructural study of cells and tissues.