1

ESSENTIALS

Unit

Introduction to A&P

ESSENTIALS

OF HUMAN

ANATOMY

& PHYSIOLOGY

The Human Body- An Orientation�Anatomy- study of the structure and

shape of the body and its parts

�Physiology- study of how the body and its parts work or function

Anatomy- Levels of Study�Gross Anatomy

� Large structures

� Easily observable

�Microscopic Anatomy

� Very small structures� Very small structures

� Can only be viewed with a microscope

Levels of Structural Organization

�Chemical level� Atoms and molecules

�Cellular level� Cells are made of molecules

�Tissue level� Tissues are made of similar types of cells� Tissues are made of similar types of cells

Levels of Structural Organization

�Organ level� Organs are different types of tissue

�Organ system level� Different organs make up organ systems

�Organism level� Organ systems make up organisms� Organ systems make up organisms

The Language of Anatomy�Special terminology is used to prevent

misunderstanding

�Exact terms are used for:

� Position

� Direction

� Regions

� Structures

Orientation

�Anatomical position� Erect� Feet shoulder width� Arms at the side� Palms facing forward

Orientation and Directional Terms

�Superior� Toward the head or upper part

of the body

� Inferior� Away from the head or upper

part of the bodypart of the body

�Anterior (ventral)� Toward or at the front of the

body; in front of

�Posterior (dorsal)� Toward or at the backside of

the body; behind

Orientation and Directional Terms

�Medial� Toward or at the midline of

the body; on the inner side of

�Lateral� Away from the midline of � Away from the midline of

the body; on the outer side of

Orientation and Directional Terms

�Proximal� Close to the point of

attachment of a limb to the body trunk

�Distal� Farther from the point of � Farther from the point of

attachment of a limb to the body trunk

Directional Terms

�Midsagittal plane� Divides the body into left

and right

�Frontal plane� Divides the body into

anterior and posterioranterior and posterior

�Transverse plane� Divides the body into

superior and inferior

Body Cavities

�Dorsal body cavity� Cranial cavity� Spinal cavity

�Ventral body cavity� Thoracic cavity� Abdominal cavity� Abdominal cavity� Pelvic cavity