Carl Ostman, age 11, of Santa Cruz, CA., for his question:
WHAT IS BIOCHEMISTRY?
Biochemistry is the study of the chemical processes that take place in all living things. Biochemists conduct research into the molecules of organic compounds that occur in the cells of animals and plants.
All organisms contain organic compounds, which are compounds containing carbon. They are called carbohydrates, lipids, nucleic acids and proteins. The molecules of these compounds help form the various structures in a cell and enable the cell to function properly.
Biochemical research covers a wide range of processes. Biochemists conduct extensive studies of large protein molecules called enzymes, which speed up chemical reactions in living matter. They identify the various enzyme molecules produced by cells and investigate the mechanism by which these molecules speed up chemical reactions.
Other research involves chemical substances that help regulate metabolism, the process by which organisms transform food into energy and new tissue.
Biochemists also study hormones, which are chemical substances produced by various parts of an organism.
Scientists in this field also seek to determine the precise role in metabolism of a nucleic acid called DNA, or deoxyribonucleic acid. Through the study of DNA, biochemistry has helped explain the molecular basis of the laws of genetics.
Molecules of DNA are present in threadlike structures called chromosomes in the nucleus of a cell. These molecules carry hereditary information from one generation of cells to the next. Thus, organisms pass hereditary traits on to their offspring.
Biochemistry has also contributed to the understanding of photosynthesis, the complex process in which green plants convert the radiant energy of the sun into the chemical energy of carbohydrates.
Biochemical research has broadened scientific knowledge in many other fields of biology and in medicine. It has also contributed to the discovery of a number of antibiotics.
Research in biochemistry has also benefited agriculture. Farmers and agricultural researchers have used findings of biochemical research to develop crops of high quality and yield.
Biochemists often use radioactive isotopes to study the chemical reactions that take place in an organism. Researchers label a molecule of a particular organic compound by substituting a radioactive isotope for one of its atoms. They then trace the isotope through a chemical reaction, using devices that detect radioactivity.
This technique has helped biochemists learn much about the complex metabolic processes that occur in animals and plants.
Electrophoresis is another method used to separate protein molecules in biochemical research. It provides an effective way of analyzing the molecular structure of blood to detect sickle cell anemia and certain other diseases.