32. Introduction to the respiratory system
32. Introduction to the respiratory system
- Gillian Pocock, Gillian PocockSenior Lecturer in Clinical Science, Canterbury Christ Church University, Canterbury, UK
- Christopher D. RichardsChristopher D. RichardsEmeritus Professor of Experimental Physiology, Division of Physiology, Pharmacology and Neuroscience, Faculty of Life Sciences, University College London, London, UK
- and David A. RichardsDavid A. RichardsAssociate Professor, Department of Basic Pharmaceutical Sciences, Husson University School of Pharmacy, Bangor, Maine, USA
Abstract
This chapter analyses the energy needed by animals for normal activities. This is mainly derived from the oxidative breakdown of foodstuffs, particularly that of carbohydrates and fats. It discusses the process called internal or cellular respiration, wherein the mitochondria oxidize carbohydrates and fatty acids generate adenosine triphosphate (ATP). The oxygen needed for this energy metabolism is ultimately derived from the atmosphere by the process of external respiration, which also serves to eliminate the carbon dioxide produced by the cells. The chapter cites the key process of external respiration, which is gas exchange between the air deep in the lungs and the blood that perfuses them. In addition to their role in gas exchange, the lungs have a variety of non-respiratory functions such as their role in trapping blood-borne particles.
