Category: 02. Introduction To The Human Body

Here is what we have learned from Introduction to the Human Body: The human body is a single structure but it is made up of billions of smaller structures of four major kinds: cells, tissues, organs, and systems. An organ is an organization of several different kinds of tissues so arranged that together they can perform…

The cavities, or spaces, of the body contain the internal organs, or viscera. The two main cavities are called the ventral and dorsal cavities. The ventral is the larger cavity and is subdivided into two parts (thoracic and abdominopelvic cavities) by the diaphragm, a dome-shaped respiratory muscle. Thoracic Cavity The upper ventral, thoracic, or chest cavity contains the heart, lungs, trachea, esophagus, large blood vessels, and nerves.…

Coronal Plane (Frontal Plane) – A vertical plane running from side to side; divides the body or any of its parts into anterior and posterior portions. Sagittal Plane (Lateral Plane) – A vertical plane running from front to back; divides the body or any of its parts into right and left sides. Axial Plane (Transverse Plane) – A horizontal plane; divides the body…

Directional terms describe the positions of structures relative to other structures or locations in the body. Superior or cranial – toward the head end of the body; upper (example, the hand is part of the superior extremity). Inferior or caudal – away from the head; lower (example, the foot is part of the inferior extremity). Anterior or ventral – front (example, the kneecap is located on the anterior side…

Before we get into the following learning units, which will provide more detailed discussion of topics on different human body systems, it is necessary to learn some useful terms for describing body structure. Knowing these terms will make it much easier for us to understand the content of the following learning units. Three groups of…

Excretion is the process that removes the waste products of digestion and metabolism from the body. It gets rid of by-products that the body is unable to use, many of which are toxic and incompatible with life.

Digestion is the process of breaking down complex ingested foods into simple molecules that can be absorbed into the blood and utilized by the body.

Respiration refers to all the processes involved in the exchange of oxygen and carbon dioxide between the cells and the external environment. It includes ventilation, the diffusion of oxygen and carbon dioxide, and the transport of the gases in the blood. Cellular respiration deals with the cell’s utilization of oxygen and release of carbon dioxide in its metabolism.

Differentiation is a developmental process by which unspecialized cells change into specialized cells with distinctive structural and functional characteristics. Through differentiation, cells develop into tissues and organs.

Growth refers to an increase in size either through an increase in the number of cells or through an increase in the size of each individual cell. In order for growth to occur, anabolic processes must occur at a faster rate than catabolic processes.