Human Anatomy Structural Levels of Organization Essay

Human Anatomy Structural Levels of Organization - Essay Example These cells appear single in simpler creatures and appear grouped in multi-cellular organisms. A group of cells constitute the tissue levels which are composed of similar cells that perform a common function. In the human body there are four basic tissues types: epithelium, muscle, connective and nervous tissue and each type perform a common function. These tissue types within the body in turn combine to form the organ level. An organ can be composed of two to four tissue types performing a specific function. The combination of tissue types allow for complex functions to be performed within the organs. Each organ such as the stomach, liver, heart and blood vessel, within the body perform a specific function which contributes to the working of the human body. In the next organ system level, certain organs work together to perform a function such as the heart and the blood vessels of the cardiovascular system as both blood circulation and pumping of the heart is required for the proper functioning of the system. The final level of organization within the human body is the organismal level which includes all the above structural components that work together to promote optimum functioning of the human body. Reference Marieb, Elaine. N. Human Anatomy & Physiology. India: Pearson Education, 1989. Google books. Web. 1 March 2011.