Demonstration

O bserve the Meissner's corpuscle with the microscope set up by the laboratory instructor. This type of receptor is abundant in the superficial dermis in outer regions of the body, such as in the fingertips, soles, lips, and external genital organs. It is responsible for the sensation of light touch. (See fig. 31.1.)

Observe the Pacinian corpuscle in the second demonstration microscope. This corpuscle is composed of many layers of connective tissue cells and has a nerve fiber in its central core. Pacinian corpuscles are numerous in the hands, feet, joints, and external genital organs. They are responsible for the sense of deep pressure (fig. 31.2). How are Meissner's and Pacinian corpuscles similar? _

How are they different? _

Sensory receptors are sensitive to changes that occur within the body and its surroundings. When they are stimulated, they initiate nerve impulses that travel into the central nervous system. As a result of the brain interpreting such sensory impulses, the person may experience particular sensations.

The sensory receptors found in skin, muscles, joints, and visceral organs are associated with somatic senses. These senses include touch, pressure, temperature, pain, and the senses of muscle movement and body position.

Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Post a comment