ANATOMY and PHYSIOLOGY

OVERVIEW

Body Plan and Organization - Homeostasis

ANATOMY

the study of structures and the relationship of structures to each other

FORM

what something looks like

where something is located

PHYSIOLOGY

the study of the functioning of specific body parts and systems

FUNCTION

how something works

what something does

Levels of Organization

Chemical Level

Cellular Level

Tissue Level

Organ Level

System Level

Organism Level

Chemical Level

atoms - compounds -molecules

all chemical substances essential for maintaining life

Cellular Level

various types and classifications of cells

each cell has a unique structure and function

Tissue Level

collection of similar cells grouped together to perform a specific function

usually derived from a common embryonic origin

Organ Level

structures that are composed of two or more different tissues

have specific functions

usually have recognizable shapes

System Level

an association of organs that have a common function

Organism Level

all parts of a body are functioning with one another as a living individual

Characteristics of Life(Life Processes)

Characteristic activities that are vital to existence of an organism

Metabolism

The sum total of all chemical processes that occur in the body

Anabolism

Using energy to synthesize or manufacture new tissue

Catabolism

The breakdown of tissue or chemical structures to produce or generate energy

Position DescriptorsDirectional Terms

Superior (Cranial)

Inferior (Caudal)

Anterior (Ventral)

Posterior (Dorsal)

Medial- Lateral

Proximal- Distal

Superficial- Deep

Planes

Fixed lines of reference along which the body is often divided to facilitate viewing a structure or describing a movement

Sagittal Plane

Divides a body or structure into right and left sections

Mid - Sagittal Plane

Divides a body or structure into equal right and left halves

Frontal (Coronal) Plane

Divides a body or structure into anterior and posterior sections

Transverse (Horizontal) Plane

Divides a body or structure into superior and inferior sections

BODY CAVITIES

Spaces within the body that contain the internal organs

Dorsal Body Cavity

Cranial Cavity

–houses the brain

Vertebral (Spinal Cavity)

–bony cavity formed by the vertebra of the spine that houses and protects the spinal cord

Ventral Body Cavity

Thoracic Cavity

–pleural cavities (2)

–mediastinum

–pericardial cavity

Abdonimopelvic Cavity

–abdominal cavity

–pelvic cavity

Abdominopelvic Quadrants and Regions

the abdominopelvic cavity can be functionally divided into quadrants and regions to more specifically identify organ locations

Abdominopelvic Quadrants

used mostly in the medical and clinical disciplines

functionally divides the abdominopelvic cavity into four quadrants

–RUQ = Right Upper Quadrant

–LUQ = Left Upper Quadrant

–RLQ = Right Lower Quadrant

–LLQ = Left Lower Quadrant

Abdominopelvic Regions

a tic-tac-toe like grid that divides the abdominopelvic cavity into nine regions

used mostly by anatomists, scientist, and academicians to more specifically identify the location of organs and other structures within the abdominopelvic cavity

Right Hypochondriac

Epigastric

Left Hypochondriac

Right Lumbar

Umbilical

Left Lumbar

Right Iliac (Inguinal)

Hypogastric (Pubic)

Left Iliac (Inguinal)

Homeostasis

An attempt by the body to maintain a constant internal environment within prescribed physiological limits

Parameters Maintained in Homeostasis

gas concentrations

temperature

pressure

pH (acidity)

nutrient concentrations

water concentrations

chemical environment

STRESS

any factor that will disrupt Homeostasis

External Stressors

heat

cold

noise

light

exercise

Internal Stressors

pain

tumors

high blood pressure

chemical imbalances

unpleasant thoughts

Homeostatic Control Systems

Nervous System

–rapid response

Endocrine System

–responds more slowly

Feedback Systems

any circular situation in which information about something is monitored and FED BACK to a control center

Components of a Feedback System

Control Center

–an area that receives information about a monitored condition and determines an appropriate response

Receptor

–an area or structure that monitors a controlled condition

Effector

–structure that produces a response or changes a controlled condition

Types of Feedback Systems

Negative Feedback System

–the response counteracts the input

–most common feedback mechanism

–examples:

blood pressure
cardiac output
temperature regulation

Positive Feedback System

–the response is intensified by the input

–breast feeding by an infant

–labor contractions during childbirth

Body Fluids

Intra-Cellular Fluid

–fluid INSIDE the cell (Cytosol)

Extra-Cellular Fluid

–fluid OUTSIDE the cell

PLASMA = fluid found within a tube
INTERCELLULAR = fluid found between cells (INTERSTITIAL fluid)

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