Introduction to Basic Human Physiology

Define physiology.
Describe the levels of function and the relationship between structure and function in the human body.
Identify the effects of fundamental laws, concepts, and forces of the Universe.
Identify processes which distinguish living from nonliving objects.
Match three somatotypes with their descriptions.
Identify general body functions.
Identify fundamental processes for providing energy to human beings.

Physiology is the study of the functions of the body at the cellular level.

Function in the human body occurs at three general levels:

Molecular

Cellular

Regional

Molecular level

The basic functional entity is the molecule. The structure and interaction of the
molecules of the body is the subject of the science of biochemistry.

Cellular level
The individual cell is the basis of the structure and function of the
human body. The human body consists of great numbers of these cells
working together as a total organism.
Groups of like cells performing a common function are called tissues.
Different tissues collected together form individual organs.
Groups of organs performing an overall function are called organ systems, for example,
the digestive system and the respiratory system.
When these systems are together in a single individual, we refer to that individual as an organism.

The cellular level of function is the primary subject matter of physiology.

Regional level
Here, individual parts of the human body (made up of specific organs) perform activities as a unit.
For example, the hand serves as a grasping, tool-holding apparatus. The study of this level of function
is called functional anatomy.


Interrelationships
There is an inseparable relationship between structure and function in the human
body.

Every structure is designed to perform a particular function or functions.
Likewise, every function has structures designed to perform it.