Those simpler invertebrates which are formed from two germ layers of ectoderm and endoderm are called diploblastic and the more developed animals whose structures and organs are formed from three germ layers are called triploblastic.
All of a triploblastic animal's tissues and organs are derived from the three germ layers of the embryo, the ectoderm, mesoderm and endoderm.
as these are the processes by which anatomy is generated over immediate (embryology) and long (evolution) timescales.
Anatomy and physiology, which study (respectively) the structure and function of organisms and their parts, make a natural pair of related disciplines, and they are often studied together.
The structure and tissues of plants are of a dissimilar nature and they are studied in plant anatomy.
The kingdom Animalia contains multicellular organisms that are heterotrophic and motile (although some have secondarily adopted a sessile lifestyle).
However, substantially the same structures and tissues are found throughout the rest of the animal kingdom and the term also includes the anatomy of other animals.
The term zootomy is also sometimes used to specifically refer to non-human animals.
It includes the appearance and position of the various parts, the materials from which they are composed, their locations and their relationships with other parts.
Anatomy is quite distinct from physiology and biochemistry, which deal respectively with the functions of those parts and the chemical processes involved.