Anatomy & PhysiologyChapter 1

Anatomy Defined

• Anatomy is the study of body structure, asking the questions: • Where is it located?• What does it look like? • How does it relate to other body parts?

• It includes microanatomy, surface anatomy, medical anatomy, histology, and cytology. Two alternate approaches are systemic anatomy and regional anatomy.

Physiology Defined

• Physiology is the study of body function, asking the question: • How does it work?

• It centers on the study of how the body adjusts of changes, and the various ways in which the body obtains and manages the use of energy.

Levels of Organization

• Chemical• Cellular• Tissue• Organ• System (Organ System)• Organism

Chemical

• Chemical level is the most

basic level of organization

• It is composed of nonliving

subunits called atoms and molecules that undergo assembly.

• Large molecules are called Macromolecules

• Small molecules are called Micro molecules

Cellular

• Cellular level is the most basic living structural level.

• It consists of cells, which are the most basic living unit.

Tissue

• Tissue level is composed of a group of similar cells that combine to perform a common function.

• The four basic types of tissues are • epithelial, • connective, • muscle, • nervous.

Organ

• Organ level consists of organs, each of which is composed of two or more different types of tissues that, when combined, perform a general function

System

• System level consists of two or more different organs that perform a more general function.

Organism

• Organism level is the most complex level of structural organization, composed of all systems that are integrated for survival of the individual.

Basic Terminology

• Medical terminology refers to the construction of new terms by the use of word parts, including:• Word roots• Prefixes• Suffixes

Directional Terminology

• Directional terminology helps to describe relative locations of body parts.

• It uses the accepted position of the body as a reference, known as the anatomical position.

Directional Terms

• Superior- toward the head• Inferior- away from the head

• Anterior- toward the front side• Posterior- toward the back

• Medial- toward the midline• Lateral- away from the midline

Directional Terms

• Superficial- surface of the body• Deep- toward the inside of the body

• For the extremities

• Proximal- closer to the core• Distal- away from the body

Sectional Planes

• Sectional planes are imaginary flat

surfaces that are useful to provide

information on sections through the

body for visual purposes.

• frontal plane, dividing the body into front and back portions;

• sagittal plane, dividing the body into right and left portions;

• transverse plane, AKA horizontal plane, dividing the body horizontally into upper and lower portions.

THE BODY PLAN

Body Regions

• Body regions are major areas of the body that are structurally distinguishable, • Head• Neck• Trunk• Upper appendages• Lower appendages

Body Cavities

• Body cavities are spaces within the body containing many of the body organs. Each cavity is lined with a membrane, and the internal organs are called visceral organs.

• Dorsal cavity: • Cranial cavity housing the brain• Vertebral canal housing the spinal cord

Ventral cavity

• The ventral cavity is devided into 2 smaller cavities,• The thoracic• The abdominopelvic

• thoracic cavity, • pericardial cavity surrounding the heart, • two pleural cavities surrounding the two lungs, and

the mediastinum superior to the heart

• Abdominopelvic cavity, • abdominal cavity housing the stomach, liver,

gallbladder, pancreas, spleen, and much of the intestines,

• pelvic cavity housing the urinary bladder, part of the intestines, and internal reproductive organs.

• The abdominopelvic cavity may also be divided into four quadrants or into nine areas.