Chapter 2: The Language of Anatomy Anatomy Unit Objectives Verbally describe or demonstrate the anatomical position. Use proper anatomical terminology to describe body directions, surfaces and body planes Locate the major body cavities, and list the chief organs in each cavity. Superficial Anatomy Involves locating structures on or near the body surface Understanding anatomical landmarks, anatomical regions, and terms for anatomical directions will help you remember both the location of a structure and its name. For example; the brachium refers to the the arm and the brachialis muscle and the brachial artery are located in the arm. Why have an anatomical position? To prevent misunderstandings, anatomists use universally accepted terms to identify body structures precisely and with a minimum of words * It is important to remember that the terms “left” and “right” refer to those sides of the person being viewed – not those of the observer. Anatomical Position 1. Body erect 2. Feet slightly apart 3. Palms facing forward 4. Thumbs point away from body 5. Similar to “standing at attention” Supine – person laying down in anatomical position face up Prone – face down Figure 1.7a Table 1.1 Table 1.1 Check Point Create 4 examples using the directional terms. 1. Share/Check with a partner. 2. Be prepared to discuss your examples. Regional Terms: Anterior View Axial: head, neck, and trunk Appendicular: arms, legs, and attachments Figure 1.7a Regional Terms: Posterior View Figure 1.7b Body Sections Sagittal – divides the body into right and left parts Midsagittal or median- sagittal plane that lies on the midline Body Sections Frontal/Coronal Section – Lengthwise plane that divides the body (or organ) into anterior and posterior Body Sections Transverse/Cross Section – Cut along a horizontal plane dividing the body or organ into superior and inferior parts. Body Planes Figure 1.8 Anatomical Variability Humans vary slightly in both external & internal anatomy. Over 90% of all anatomical structures match textbook descriptions, but: - Nerves or blood vessels may be somewhat out of place - Small muscles may be missing Extreme anatomical variations are seldom seen . . . But it does happen… Body Cavities Dorsal Body Cavity 1. Cranial Cavity – Brain 2. Vertebral Cavity – Spinal cord & nerve origins Ventral Body Cavity 1. Thoracic Cavity – Chest cavity A. Pleural Cavity – Lungs B. Pericardial Cavity – Heart C. Mediastinum 2. Abdominopelvic Cavity A. Abdominal – stomach, spleen, gallbladder, liver, pancreas, small & large intestines B. Pelvic – bladder, portions of large intestines, sex organs Body Cavities Body Cavities The Dorsal cavity protects the nervous system, and is divided into two subdivisions: ◦ Cranial cavity is within the skull and encases the brain ◦ Vertebral cavity runs within the vertebral column and encases the spinal cord Body Cavities Ventral cavity houses the internal organs and is divided into two subdivisions: 1. Thoracic 2. Abdominopelvic Body Cavities The Thoracic cavity is subdivided into : Pleural cavities – each houses a lung Mediastinum – contains the pericardial cavity, and surrounds the remaining thoracic organs Pericardial cavity – encloses the heart Body Cavities The abdominopelvic cavity is separated from the superior thoracic cavity by the dome-shaped diaphragm Two subdivisions: ◦ Abdominal cavity – contains the stomach, intestines, spleen, liver, and other organs ◦ Pelvic cavity – lies within the pelvis and contains the bladder, reproductive organs, and rectum Ventral Body Cavity Membranes Parietal serosa lines internal body walls Visceral serosa covers the internal organs Serous fluid separates the serosae Ventral Body Cavity Membranes Figure 1.10a Other Body Cavities 1. Oral and digestive – mouth and cavities of the digestive organs 2. Nasal - located within and posterior to the nose 3. Orbital – house the eyes 4. Middle ear – contain bones (ossicles) that transmit sound vibrations 5. Synovial – joint cavities Other Body Cavities Abdominopelvic Regions Umbilical Epigastric Hypogastric Right and left iliac or inguinal Right and left lumbar Right and left hypochondriac Figure 1.11a Abdominopelvic Regions Umbilical – Centermost region deep to and surrounding the umbilicus. Epigastric- located superior to the umbilical region Hypogastric- located inferior to the umbilical region Abdominopelvic Regions Right and left iliac (inguinal)located lateral to the hypogastric region. Right and left lumbar-lie lateral to the umbilical region. Right and left hypochondriac- lie lateral to the epigastric region. Organs of the Abdominopelvic Regions Figure 1.11b Abdominopelvic Quadrants Right upper Left upper Right lower Left lower Figure 1.12 At the clinic 1. This cavity contains the bladder and the rectum. 2. Which body cavity protects the nervous system? 3. The frontal section is also called what? 4. This region is inferior to the lumbar region. 5. This region is superior to the hypogastric region.