Chapter 1

Anatomy

Anatomy

The study of the structure of body parts and their relationship to one another

Physiology

Study of the function of body parts; how they work to carry out life-sustaining activities

Gross/macroscopic anatomy

The study of large, visible structures

Microscopic anatomy

Deals with structures to small to be seen by the naked eye

Developmental anatomy

Studies anatomical and physiological development throughout life

Chemical level

atoms, molecules and organelles

Cellular level

single cell

Tissue level

groups of similar cells

Organ level

contains two or more types of tissues

Organ system level

organs that work closely together

Organismal level

all organ systems combined to make the whole organism

Maintenance of life involves:

-maintaining boundaries -movement -responsiveness -digestion -metabolism -excretion -reproduction -growth

Maintaining boundaries

Separation between internal and external environments must exist

Movement

Muscular system allows for this

Contractility

Movement at the cellular level

Responsiveness

ability to sense and respond to stimuli

Digestion

Breakdown of ingested foodstuffs, followed by absorption of simple molecules into blood

Metabolism

All chemical reactions that occur in body cells

Excretion

Removal of wastes from metabolism and digestion

Reproduction

At the cellular level, this involves division of cells for growth and repair

Growth

Increase in size of a body part or organism

Survival needs:

-nutrients -oxygen -water -normal body temperature -appropriate atmospheric pressure

Homeostasis

The maintenance of relatively stable internal condition despite continuous changes in environement

Receptor

-sensor -responds to stimuli -monitors environment

Control center

-receives input from receptor -determines appropriate response

Effector

-receives output from control center -provides the means to respond -provides either a negative or positive feedback

Negative feedback

-most used feedback mechanism in the body -response reduces or shuts off original stimulus

ex. regulation of body temp; regulation of glucose by insulin

Positive feedback

-response enhances or exaggerates the original stimulus -usually controls infrequent events that do not require continuous adjustment

ex. enhancement of labor contractions by oxytocin

Homeostasis imbalance

-increases risk of disease -contributes to changes associated with aging -if negative feedback mechanisms become overwhelmed, destructive positive feedback mechanisms may take over

ex. Heart failure

Superior (cranial)

Towards the head end or upper end of the body

Inferior (caudal)

Away from the head end or toward the lower part of a structure of a body

Anterior (ventral)

Toward or at the front of the body

Posterior (dorsal)

Toward or at the back of the body

Medial

Toward or at the midline of the body

Lateral

Away from the midline of the body

Intermediate

Between a more medial and a more lateral structure

Proximal

Closer to the origin of the body part or the point of attachment of a limb to the body trunk

Distal

Farther from the origin of a body part or the point of attachment of a limb to the body trunk

Superficial (external)

Toward or at the body surface

Deep (internal)

Away from the body surface

Coronal/frontal plane

Separates anterior and posterior structures

Sagittal/lateral plane

Separates the right and left side of the body

Axial/transverse plane

Separates superior and inferior structures

Oblique plane

Separated diagonally