Medical Terminology Lecture 8 (PDF)

Theory three Medical Terminology First stage Organization of the Body The human body consists of several structural and functional levels of organization. The complexity of each level increases from one to the next....

Theory three Medical Terminology First stage Organization of the Body The human body consists of several structural and functional levels of organization. The complexity of each level increases from one to the next. Levels of Structural Organization in the Human Body The human body has six main levels of structural organization. The levels of organization from the least to the most complex are the: 1. Chemical level It is the simplest level within the structural hierarchy. The chemical level includes the tiniest building blocks of matter, atoms, which combine to form molecules, like water. In turn, molecules combine to form organelles, the internal organs of a cell pg. 1 ‫م علي ماجد‬.‫م‬ ‫م محمد طالل‬.‫م‬ ‫م سرى ستار‬.‫م‬  Theory three Medical Terminology First stage 2. Cellular level The cellular level is made up of the smallest unit of living matter, the cell. Cells are the most basic structural unit of all living organisms. Individual cells may have some common functions but vary widely in size and shape. Each type of cells carries out a set of unique tasks within the human body.  The basic structural terms of a cell include: o A cell membrane that allows certain substances in and out. o A nucleus that directs activities within the cell. o Mitochondria that generate energy for the cell. o Cytoplasm that is a watery fluid that fills the spaces outside the nucleus. 3. Tissue level Tissues are groups of similar cells that have a common function. Cells make up tissues, which are composed of similar cells working together to perform similar tasks. A tissue must contain two different types of cells. The four basic tissue types in humans include epithelium, connective, muscle, and nervous tissue. 4. Organ level An organ is a structure composed of at least two different tissue types that perform a specific function within the body. Examples include the brain, stomach, bladder, and liver. Complex functions begin to emerge at this level. pg. 2 ‫م علي ماجد‬.‫م‬ ‫م محمد طالل‬.‫م‬ ‫م سرى ستار‬.‫م‬  Theory three Medical Terminology First stage 5. System level One or more organs work in harmony to accomplish a common purpose. Meaning that a system is a group of organs and tissues that work together to perform important functions of the body. For example, in the cardiovascular system the heart and blood vessels work together and circulate blood throughout the body to provide oxygen and nutrients to cells. Besides the cardiovascular system, the other organ systems of the body are the integumentary, skeletal, nervous, muscular, endocrine, respiratory, lymphatic, digestive, urinary, reproductive systems. 6. Organismal level The organismal level is the highest or most complex level of organization. It is the sum of all structural levels working together. In short, it is the human being (or organism) as a whole. pg. 3 ‫م علي ماجد‬.‫م‬ ‫م محمد طالل‬.‫م‬ ‫م سرى ستار‬.‫م‬  Theory three Medical Terminology First stage BASIC STRUCTURAL UNITS Word Meaning Word Analysis Element chondr/o cartilage chondr/oma: tumor of the cartilage -oma: tumor cyt/o/meter: Instrument for counting and measuring cells cyt/o cell -meter: instrument for measuring cyt/o/toxic: Substance that is destructive to cells -toxic: poison hist/o/lysis: separation; destruction; or loosening of hist/o tissue tissue -lysis: separation; destruction; loosening nucle/ar: pertaining to a nucleus -ar: nucle/o nucleus pertaining to BODY POSITION AND DIRECTIONAL TERMS Word Element Meaning Superior towards the top of the body. (cranial) Inferior towards the bottom of the body. (caudal) Anterior towards the front of the body (ventral) Posterior towards the back of the body (dorsal) Medial towards the midline(center) of the body Lateral away from the midline of the body Proximal situated closest to the point of attachment Distal situated farthest from the point of attachment Superficial on or close to the surface of the body. Deep Farther away from the surface of the body. pg. 4 ‫م علي ماجد‬.‫م‬ ‫م محمد طالل‬.‫م‬ ‫م سرى ستار‬.‫م‬  Theory three Medical Terminology First stage  What are the names of the two main body cavities? The two major body cavities, one in the front of the body and one in the back, The front body cavity is called the ventral cavity. The cavity in the back of the body is called the dorsal cavity.  The two major body cavities and their subdivisions A) Ventral cavity 1. Thoracic 2. Abdominopelvic B) Dorsal cavity 1. Cranial 2. Spinal pg. 5 ‫م علي ماجد‬.‫م‬ ‫م محمد طالل‬.‫م‬ ‫م سرى ستار‬.‫م‬