Summary

Summary

Anatomy is the science of body structures and the relationships among these structures. Physiology is the science of body functions. The human body consists of six levels of structural organization: chemical, cellular, tissue, organ, system, and organism levels. Certain processes that distinguish life processes from nonliving things include metabolism, responsiveness, movement, growth, differentiation, and reproduction. Essentials for life include body boundaries, movement, responsiveness, digestion, metabolism, excretion, reproduction, and growth. Survival requires nutrients, water, oxygen, atmospheric pressure, and the maintenance of adequate body temperature. Homeostasis of the body is controlled by receptors, effectors, and a set point that is achieved by the control center of the body (which primarily uses the nervous and endocrine systems).

The abdomen and pelvis are divided into nine abdominopelvic regions: left hypochondriac, epigas-tric, right hypochondriac, left lumbar, umbilical, right lumbar, left iliac (inguinal), hypogastric, and right iliac (inguinal).

Body cavities are mainly divided into two sections: dorsal cavity and ventral cavity. The dorsal cavity is subdivided into the cranial cavity (which contains the brain) and the vertebral cavity or canal (which contains the spinal cord). The meninges are protective tissues that line the dorsal body cavity. The ventral body cavity is subdivided by the diaphragm into a superior thoracic cavity and an inferior abdom-inopelvic cavity. The viscera are organs within the ventral cavity, also called the coelom. A serous membrane lines the wall of the cavity and adheres to the viscera. The thoracic cavity is subdivided into three smaller cavities, the pericardial cavity, the mediasti-num, and the pleural cavity.

The body’s organ systems work together to maintain homeostasis. These systems include the integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, digestive, respiratory, urinary, and reproductive systems. The body’s anatomic planes include the coronal (frontal), sagittal, and transverse (horizontal) planes.