Pituitary Gland and its Relation to the Hypothalamus Anterior and Posterior Lobes of The Pituitary Gland The pituitary gland ( Figure 76-1 ), also called the hypophysis, is a small gland—about 1 centimeter in diameter and 0.5 to 1 gram…
Coordination of Body Functions by Chemical Messengers The multiple activities of the cells, tissues, and organs of the body are coordinated by the interplay of several types of chemical messenger systems: 1. Neurotransmitters are released by axon terminals of neurons…
Normal Body Temperatures Body Core Temperature and Skin Temperature The temperature of the deep tissues of the body—the “core” of the body—usually remains very constant, within ±1°F (±0.6°C), except when a person has a febrile illness. Indeed, a nude person…
Adenosine Triphosphate Functions as an “Energy Currency” in Metabolism Carbohydrates, fats, and proteins can all be used by cells to synthesize large quantities of adenosine triphosphate (ATP), which is used as an energy source for almost all other cellular functions.…
Energy Intake And Output are Balanced Under Steady-State Conditions Proteins, carbohydrates, and fats in the diet provide energy for various body functions or for storage and later use. Stability of body weight and composition over long periods requires that a…
Although the liver is a discrete organ, it performs many different interrelating functions. The critical interrelated functions of the liver become especially evident when abnormalities of the liver occur. This chapter summarizes some of the major functions of the liver,…
About three-quarters of the body solids are proteins. These proteins include structural proteins, enzymes, nucleoproteins, proteins that transport oxygen, proteins of the muscle that cause muscle contraction, and many other types that perform specific intracellular and extracellular functions throughout the…
Several chemical compounds in food and in the body are classified as lipids, including the following: (1) neutral fat , also known as triglycerides; (2) phospholipids; (3) cholesterol; and (4) a few others of less importance. Chemically, the basic lipid…
The next few chapters deal with metabolism in the body—the chemical processes that make it possible for the cells to continue living. It is not the purpose of this text to present the chemical details of all the various cellular…
Effective therapy for most gastrointestinal disorders depends on a basic knowledge of gastrointestinal physiology. The purpose of this chapter is to discuss a few representative types of gastrointestinal malfunction that have special physiological bases or consequences. Disorders of Swallowing and…