Human Anatomy and Physiology - I. V. Gayvoronsky 2011

The Human Organism as a Single Whole. Basics of Cytology and Histology
Organ Systems

An organ system is an integration of various Organs united by the performance of common Functions. The following organ systems are distinguished:

1) The Musculoskeletal System;

2) the Digestive System;

3) the Respiratory system;

4) The Cardiovascular system;

5) the Urinary System;

6) the Reproductive System (male, female);

7) the Endocrine System;

8) The Nervous system;

9) the somatosensory (integumentary) system.

Major organ systems may include subsystems. For example, the Components of the cardiovascular system include The Heart, as well as the arterial, venous, lymphatic, and microcirculatory systems.

Organs belonging even to the same system differ significantly in their Structure. For instance, within the digestive system, organs such as the Teeth, Tongue, Esophagus, and Liver are completely different in their shape, Location, color, consistency, and internal structure. The unity and integrity of an organ system are determined primarily by the common direction of physiological processes.

However, most organs within the same system share a common structural plan. Thus, in the digestive system, the Pharynx, esophagus, Stomach, and small and large intestines share common principles of wall structure. They comprise the mucosal, muscular, and serous (adventitial) layers, although each of them also features typical structural characteristics. These Organs of the digestive system perform a shared function: the Digestion of food and the absorption of the resulting substances.

Thus, an organ system implies, above all, the functional integration of organs.