INTRODUCCIÓN AL METABOLISMO. Catabolismo Anabolismo Autótrofos Heterótrofos

Video PDF: http://www.mediafire.com/view/9e4ebzf... INTRODUCTION TO METABOLISM. CATABOLISM, ANABOLISM, CHAINED AND ENERGY-COUPLED REACTIONS, AUTOTROPHS AND HETEROTROPHS Living beings are dynamic systems that are continuously exchanging and transforming matter in the environment. This occurs through countless reactions carried out in the aqueous environment within organisms. Metabolism can be defined as the set of biochemical reactions that process changes in matter in living beings. TYPES OF METABOLISM 1. CATABOLISM  Degradation of organic matter in which energy is released. 2. ANABOLISM  Synthesis of organic matter that requires an energy input Each sequence or set of reactions that lead to the production of one or more specific substances is known as a metabolic pathway. Metabolic pathways are characterized by: 1. They are linked, meaning the metabolites of one can be the start of another. This creates a vast and complex metabolic map in which all pathways can be interrelated. 2. They are regulated by specific biocatalysts or enzymes. 3. They are energetically coupled. This means that the energy released in overall reactions is used, thanks to energy transporters such as ATP, in energy-requiring reactions (endothermic). Depending on the general type of metabolism, two types of organisms are distinguished: a) AUTOTROPHS. The source of the carbon needed to synthesize their own biomolecules is inorganic (CO2). If the energy required for the process is light, they are called photosynthetic or photolithotrophs; if it is chemical, they are called chemosynthetic or chemolithotrophs. This is the case with plants. b) HETEROTROPHS. The carbon source for synthesizing their own matter comes from other living beings (organic matter). A typical example is animals.