19. Biochemistry

Biochemistry is a fascinating and vital field of chemistry that explores the chemical processes within and related to living organisms. In the ENEM context, it is essential to have a solid understanding of biochemistry to answer questions related to this area. This chapter will guide you through the fundamental concepts of biochemistry, from the structure and function of biomolecules to metabolism and bioenergetics.

Biomolecules

Biomolecules are the chemical components that make up living organisms. They are classified into four main categories: carbohydrates, lipids, proteins and nucleic acids.

Carbohydrates

Carbohydrates are composed of carbon, hydrogen, and oxygen. They are the main source of energy for most organisms and also play a structural role in many of them. Carbohydrates include simple sugars such as glucose and fructose and complex sugars such as starch and cellulose.

Lipids

Lipids are water-insoluble molecules that are essential for many biological functions, including energy storage, insulation, protection, and cell signaling. Lipids include fats, oils, waxes, phospholipids and steroids.

Proteins

Proteins are polymers of amino acids and are responsible for a wide variety of functions, including catalyzing metabolic reactions, replicating DNA, responding to stimuli, and transporting molecules from one location to another. There are 20 different amino acids that can combine to form a protein.

Nucleic Acids

Nucleic acids, DNA and RNA, are the molecules that carry the genetic information in all living organisms. They are composed of nucleotides, which include a nitrogenous base, a sugar and a phosphate group.

Metabolism

Metabolism refers to the set of chemical reactions that occur within a cell to maintain life. It is divided into two categories: catabolism, which is the breakdown of molecules to obtain energy, and anabolism, which is the synthesis of all the compounds needed by cells.

Glycolysis and the Krebs Cycle

Glycolysis is the process of breaking down glucose to produce energy in the form of ATP. The Krebs cycle, also known as the citric acid cycle, is a series of chemical reactions used by all aerobic cells to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats and proteins.

Bioenergetics

Bioenergetics is the study of how energy flows through living organisms. It is a fundamental area of ​​biochemistry that describes how cells transform energy, usually in the form of ATP, to carry out their functions.

Understanding biochemistry is crucial to understanding life at a molecular level. This knowledge is fundamental to the study of biology and is an integral part of many fields of science, including medicine, genetics and biotechnology. In the ENEM context, a solid understanding of biochemistry can help you answer a variety of questions, from those that test your basic knowledge of biomolecules to those that require a deeper understanding of metabolic and bioenergetic processes.