Biochemistry
Fifteen to twenty billion years ago, the universe arose as a cataclysmic eruption of hot, energy-rich sub-atomic particles. Within seconds, the simplest elements
(hydrogen and helium) were formed. As the universe expanded and cooled, material condensed under the in-fluence of gravity to form stars. Some stars became enormous and then exploded as supernovae, releasing the energy needed to fuse simpler atomic nuclei into the more complex elements. Thus were produced, over bil-lions of years, the Earth itself and the chemical elements found on the Earth today. About four billion years ago, life arose—simple microorganisms with the ability to ex-tract energy from organic compounds or from sunlight, which they used to make a vast array of more complex biomolecules from the simple elements and compounds on the Earth’s surface.
Biochemistry asks how the remarkable properties of living organisms arise from the thousands of differ-ent lifeless biomolecules. When these molecules are iso-lated and examined individually, they conform to all the physical and chemical laws that describe the behavior of inanimate matter—as do all the processes occurring in living organisms. The study of biochemistry shows how the collections of inanimate molecules that consti-tute living organisms interact to maintain and perpetu-ate life animated solely by the physical and chemical laws that govern the nonliving universe.
Yet organisms possess extraordinary attributes, properties that distinguish them from other collections of matter. What are these distinguishing features of liv-ing organisms?
A high degree of chemical complexity and microscopic organization. Thousands of differ-ent molecules make up a cell’s intricate internal structures (Fig. 1–1a). Each has its characteristic sequence of subunits, its unique three-dimensional structure, and its highly specific selection of binding partners in the cell.
Systems for extracting, transforming, and using energy from
(hydrogen and helium) were formed. As the universe expanded and cooled, material condensed under the in-fluence of gravity to form stars. Some stars became enormous and then exploded as supernovae, releasing the energy needed to fuse simpler atomic nuclei into the more complex elements. Thus were produced, over bil-lions of years, the Earth itself and the chemical elements found on the Earth today. About four billion years ago, life arose—simple microorganisms with the ability to ex-tract energy from organic compounds or from sunlight, which they used to make a vast array of more complex biomolecules from the simple elements and compounds on the Earth’s surface.
Biochemistry asks how the remarkable properties of living organisms arise from the thousands of differ-ent lifeless biomolecules. When these molecules are iso-lated and examined individually, they conform to all the physical and chemical laws that describe the behavior of inanimate matter—as do all the processes occurring in living organisms. The study of biochemistry shows how the collections of inanimate molecules that consti-tute living organisms interact to maintain and perpetu-ate life animated solely by the physical and chemical laws that govern the nonliving universe.
Yet organisms possess extraordinary attributes, properties that distinguish them from other collections of matter. What are these distinguishing features of liv-ing organisms?
A high degree of chemical complexity and microscopic organization. Thousands of differ-ent molecules make up a cell’s intricate internal structures (Fig. 1–1a). Each has its characteristic sequence of subunits, its unique three-dimensional structure, and its highly specific selection of binding partners in the cell.
Systems for extracting, transforming, and using energy from