北京大学.生物化学.2005 (5).pptVIP

Instructors for Biochemistry II Dr. Yongmei Qin (秦咏梅，Associate Professor, director of Biochemistry II) Tel.:6275-8885 (office); Room 214, New Life Science Building; E-mail: qinym@ Dr. Zengyi Chang (昌增益, Professor） Tel: 6275-8822 (office); Room 204, New Life Science Building; E-mail: changzy@ Teaching Assistants for Biochemistry II Ruiyu Kang (康瑞玉)：6275-8056 Raymank@ Fangyuan Chen (陈方圆): faye@ Anastasia Ngozi(阿娜莎)anasha@ How the nutrients that we are ingesting daily become part of our body and allow growth to occur (what is the fate of the sugar, fat, protein and nucleic acids that enter our body along with the food ?) Why do we become fat by only eating sugar? What is the molecular nature of the large number of genetic diseases? How can we find ways to prevent and treat them? What does O2 do for us? And how is O2 produced by plants? How do the various living organisms “produce” and “consume” energy? … Biochemistry IIMetabolism: The totality of the transformation of biomolecules (matter) and energy Definition of Metabolism The entire highly integrated and regulated network of chemical transformations (as stepwise metabolic pathways catalyzed by many enzymes) occurring in a living organism (through which cells extract energy and reducing power from its environment, as well as synthesize the building blocks of its macromolecules and then the macromolecules themselves). For maps of metabolic pathways see: / metabolism is categorized into two types Catabolism (biodegradation): larger molecules (nutrients and cell constituents) are broken down (often via exergonic reactions) to salvage (reuse) their components or/and to generate energy. Anabolism (biosynthesis): The generation of biomolecules from simpler components (often via endergonic reactions). Major Roles of Metabolism Extract energy and reducing power from the environment (photosynthesis and oxidative degradation of nutrients). Generation (interconversion) of all the biomolecules fo