Intro to Anatomy

• Anatomy is the study of the structures of body parts and their relationship to one another.
• Physiology is the study of the function of body systems.
• Structure determines the function.
• The Anatomical position is standing erect, facing forward, palms facing forward.
• Superior means above; Inferior means below.

  Anterior means front; posterior means back.

  Medial means towards midline; lateral means away from midline.

  Proximal means toward origin; distal means away from origin.

  Superficial means toward surface; deep means away from surface.

  Bilateral is paired right/left structures; Unilateral is unpaired structures.

  Ipsilateral is same side; contralateral is opposite sides.
• There are three body planes, the sagittal, coronal, and transverse.

  The sagittal is a vertical cut into right and left halves.

  The coronal is a vertical cut into front and back halves.

  The transverse is a cross sectional cut.
• There are two main body cavities, the dorsal and ventral.

  The dorsal cavity contains the cranial and vertebral cavities.

  The ventral cavity contains two different main cavities, the thoracic and abdominopelvic.

  The Thoracic contains the pleural and mediastinum cavities.

  The pleural contains the lungs. The mediastinum contains the pericardial cavity, esophagus, and aorta.

  The Abdominopelvic contains the abdominal and pelvic cavities.
• Body is 70% water, and water is found within many areas including intra-cellular and extra-cellular. Intracellular fluid is fluid within the cell, and Extracellular fluid is fluid outside the cell. There are two kinds of extracellular fluid, interstitial and plasma. Interstitial fluid is fluid between cells, and plasma is fluid in blood vessels. Conditions regarding the placement of fluid are: Edema, which is swelling, or an abnormal shift of fluid between compartments INTO interstitial space. Dehydration is loss of fluid from extracellular space. Hemorrhage is loss of fluid from plasma.
• Homeostasis is the body’s ability to maintain a relatively stable internal environment. A constant communication between body systems is needed in order to do this. Control systems are the nervous system and endocrine system. Feedback is the communication of information in the body. Negative feedback is a reaction opposite of the change (indirect relationship). Positive feedback (NOT COMMON) is a reaction the same of the change (direct relationship).
• Sensory nerve cells send feedback, and motor nerve cells carry out responses.