PATHOLOGY

Detailed explanation-1: -Since humans develop from a single cell upon fertilization, there must be a process of creating these different types of cells needed for organs. Hence, the process of cell differentiation.

Detailed explanation-2: -Division of cells during the early embryo stages is known as cleavage in embryology. Fertilization is followed by cleavage.

Detailed explanation-3: -In the adult body, Hox genes are among others responsible for driving the differentiation of tissue stem cells towards their respective lineages in order to repair and maintain the correct function of tissues and organs.

Detailed explanation-4: -Thus the position (location) of a cell in the early embryo largely determines what cell type it will become in the end of the process of the embryonic development. The process of altering the pattern of gene expression and thus becoming a cell of a particular type is called cell differentiation.