Apical (anatomy)

Apical (anatomy) refers to the anatomical term used to describe something situated away from the point of origin or attachment. In the context of cellular biology, the term 'apical' is used to refer to the 'top' or 'tip' of a cell, structure, or organ. This term is used in contrast to the term 'basal' or 'base', which refers to the bottom or base of a structure.

Overview

The apical membrane of a polarized cell is the surface of the cell that faces away from the basement membrane. This is particularly relevant in the context of epithelial cells, which are often polarized, meaning they have a distinct 'top' (apical) and 'bottom' (basal). The apical side of an epithelial cell is the side that faces the lumen of an organ (such as the inside of the gut or the outside of the body), while the basal side is the side that faces the underlying cells and tissues.

Apical in Different Systems

In the nervous system, 'apical' can refer to the apical dendrite of a pyramidal neuron, which is a dendrite that extends from the apex of the neuron's cell body. Similarly, in the cardiovascular system, 'apical' can refer to the apex of the heart, which is the tip of the left ventricle, opposite the base of the heart.

Apical in Cellular Biology

In cellular biology, the apical surface of a cell is the one facing the lumen of an organ or the external environment, as opposed to the basal surface. This is particularly important in epithelial cells, which line the surfaces of structures throughout the body and have distinct functional and structural differences between their apical and basal surfaces.

See Also

• Basal (anatomy)
• Polarity (biology)
• Epithelial cells
• Apical dominance