In the glucose molecule, the chemical bonds between the. carbon (C) and hydrogen (H) atoms hold energy from the sun. 1. When our. bodies extract energy from food and convert it to a form that our cells can. use, we lose more than half of the total food energy as heat.
These secretions flow to the surface of the body or to the lining of a hollow structure in the body. The exocrine secretions are involved in many important functions, such as sweating, digestion and lubricating the eyes.There are many types of exocrine glands in the exocrine system.xamples include the salivary glands, liver, stomach, prostate, lacrimal glands, pancreas, sweat glands, sebaceous glands, and mammary glands. A few examples of conditions that afflict the exocrine system include infection, ulcer, cancer, tumors, obstruction, genetic conditions and sebaceous cysts.
The absorptive surface area of the small intestine is increased by plicae circulares, villi, and microvilli. Exocrine cells in the mucosa of the small intestine secrete mucus, peptidase, sucrase, maltase, lactase, lipase, and enterokinase.Endocrine cells secrete cholecystokinin and secretin. The most important factor for regulating secretions in the small intestine is the presence of chyme.he small intestine is divided into the duodenum, jejunum, and ileum. The small intestine follows the general structure of the digestive tract in that the wall has a mucosa with simple columnar epithelium, submucosa, smooth muscle with inner circular and outer longitudinal layers, and serosa.