Final answer:
Histology is the study of the shape and arrangement of cells in tissue, which are the smallest units of life.
Step-by-step explanation:
The analysis of the smallest units of life is called histology. Histology is the study of the shape and arrangement of cells in tissue. All cells and tissues in the body derive from three germ layers in the embryo: the ectoderm, mesoderm, and endoderm.