Orientation to the Human Body


afferent nerve

sensory nerve that sends information about the body and its environment to the brain


the study of the structure and form of an organism


process of listening to sounds that the body produces, usually with the aid of a stethoscope, in order to gain information about the body

efferent nerve

nerve that carries information from the brain to the rest of the body


the process of ridding the body of metabolic waste products

extracellular matrix

molecular framework secreted by cells that supports them structurally and biochemically


the study of an organism's tissue structure under a microscope


the body's processes to physiologically regulate its internal environment with response to fluctuations that occur in the internal or external environment

integrating center

control center that integrates information received from receptors to determine an appropriate response or set point


on a molecular level, the biological processes that build or break molecules; on an organismal level, all of the chemical reactions within an organism that provide cells with the capacity to acquire energy and use that energy to carry out different functions

negative feedback

homeostatic feedback system that counteracts a stimulus by inhibiting the direction of the stimulus


structure, formed from more than one tissue, with a specific function

organ systems

group of organs with a common function


the study of the function of organs and organ systems under both normal and altered conditions

positive feedback

homeostatic feedback system that maintains a stimulus, often increasing the action of a stimulus


protein to which signaling molecules can bind to elicit a physiological response

set point

value where the physiological state of the body is stable


change in the internal or external environment contributing to fluctuations that occur away from the set point


the regulation of a body's internal temperature


specialized cells that are grouped together to perform a common function


the constriction, or narrowing, of blood vessels


the dilation, or widening, of blood vessels