Body plan

• Most anatomical terms are derived from Latin or Greek
• For example, foramen is a Latin word for “hole,” and magnum means “large”
• The foramen magnum is a large hole in the skull through which the spinal cord attaches to the brain
• Prefixes and suffixes can be added to words to expand their meaning
• For instance, the suffix -itis means an inflammation, so appendicitis is an inflammation of the appendix
• Anatomical position refers to a person standing erect with the face directed forward, the upper limbs hanging to the sides, and the palms of the hands facing forward
• Toes pointing forward
• A person is supine when lying face upward and prone when lying face downward
• Directional terms describe parts of the body relative to each other
• Right and left are used as directional terms in anatomical terminology
• Superior means above, and inferior means below
• Anterior is used for “in front of,” and posterior is used for “behind”
• Lateral means “sideway,” and medial means “midline of the body”
• Superficial is toward the body surface, and deep is toward the inner part of the body
• Proximal means “close to,” whereas distal means “far from”
• Medial means “toward the midline,” and lateral means “away from the midline”
• The body is subdivided into central regions: head, neck, and trunk
• The trunk has three regions: thorax, abdomen, and pelvis
• The upper limb consists of the arm, forearm, wrist, and hand
• The lower limb includes the thigh, leg, ankle, and foot
• The abdomen is often subdivided superficially into quadrants by two imaginary lines— one horizontal and one vertical—that intersect at the navel
• Quadrants formed are the right-upper, left-upper, right-lower, and left-lower quadrants
• Sometimes subdivided into regions by four imaginary lines, resulting in nine regions
• Planes are imaginary flat surfaces that divide the body
• Sagittal plane separates the body into right and left halves
• Transverse (horizontal) plane divides the body into superior and inferior portions
• Frontal (coronal) plane divides the body into front (anterior) and back (posterior) halves
• The body contains two types of internal cavities: the dorsal body cavity and the ventral body cavity
• The dorsal body cavity encloses the brain and spinal cord
• The ventral body cavity houses the majority of internal organs, with two major subdivisions: thoracic cavity and abdominopelvic cavity
• The thoracic cavity houses the heart and lungs, further subdivided into pleural cavities and mediastinum
• The abdominopelvic cavity contains the abdominal and pelvic cavities, with organs housed within the peritoneal cavity
• Serous membranes line the walls of body cavities and cover internal organs, with parietal and visceral layers
• Inflammation of serous membranes in the ventral body cavities can lead to conditions like pericarditis, pleurisy, and peritonitis