Body Planes Anatomic reference systems describe the location and functions of body parts. The basic reference systems are: body planes, body directions, body cavities, and structural units Body planes are imaginary horizontal and vertical lines used to divide the body into sections The use of these planes makes it easier to describe the location of an organ or problem.

Midline and Bilateral Symetery The midline, also known as the midsagittal plane, is a vertical plane that divides the body, into equal left and right halves.

Transverse Plane The transverse plane, also known as the horizontal plane, divides the body into superior (upper) and inferior (lower) portions.

Ventral and Dorsal Ventral refers to the front or belly side of the body. Dorsal refers to the back of the body.

Superior and Inferior Superior means uppermost, above or toward the head. For example, the lungs are located superior to (above) the diaphragm. Inferior means lowermost, below or toward the feet. For example, the stomach is located inferior to (below) the diaphragm.

Body Cavities Dorsal Cavity Ventral Cavity Terms Related to Abdominal Cavity

Body Cavities Cranial Thoracic Spinal Diaphragm Adbdominal Pelvic

Body Cavities The dorsal cavity contains the structure of the nervous system that coordinate the bodily functions. The dorsal cavity is divided into the cranial cavity, which contains the brain, and the spinal cavity, which contains the spinal cord. The ventral cavity contains the body organs that maintain homeostasis. Homeostasis means maintaining a constant internal environment. The ventral cavity is divided into three parts: thoracic, abdominal, and pelvic cavities.

Divisions of the Spinal Cord Cervical vertebrae: C Thoracic vertebrae: T Lumbar vertebrae: L Sacrum: S Spinal column or spinal cord Disk (slipped disk) FLASH MOVIE -- CLICK

Lecture Slides in PowerPoint by Jerry L. Cook MEMBRANES Lecture Slides in PowerPoint by Jerry L. Cook Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Mucous Membranes Lines all body cavities that open to the exterior Line the digestive, respiratory, urinary and reproductive systems Loose connective tissue underneath Often adapted for secretion ex. Line the stomach Slide 4.4

Serous Membranes Line thoracic / abdominal cavities & keep everything “wet” / lubricated Surface simple squamous epithelium Ex. Sac around heart = pericardial sac Ex. Sac around lungs = pleural membranes Slide 4.5

Synovial Membranes Connective Tissue have membranes Lines fibrous capsules surrounding joints Bursitis is inflammation of membranes and sacs in the knee Figure 4.2 Slide 4.7

Basic Features of the Nervous System Meninges: The three layers of tissue that encase the central nervous system; the dura mater, arachnoid membrane, and the pia mater. Dura mater: Outermost, tough and flexible. Arachnoid membrane: Middle layer located between the dura mater and pia mater. Pia mater: Innermost layer of the meninges that clings to the surface of the brain; thin and delicate.

[Blood vessels and Cerebrospinal Fluid (CSF)] Dura Mater Arachnoid Membrane Subarachnoid Space [Blood vessels and Cerebrospinal Fluid (CSF)] Pia Mater Nervous System Tissue Brain, spinal cord, cranial nerves, spinal nerves, peripheral ganglia

Cutaneous Membrane Cutaneous membrane = skin Superficial epidermis A dry membrane Outermost protective boundary Superficial epidermis Keratinized stratified squamous epithelium Underlying dermis Mostly dense connective tissue Figure 4.1a Slide 4.3 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings