This field deals with the cell structure and function in detail. Many biologically active molecules contain one or more functional groups. Progress. A variety of biologically relevant compounds contain methyl groups like those highlighted above. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Sometimes, the compound can have a methyl group but still be a polar compound overall because of the presence of other functional groups with polar properties (see the discussion on polar functional groups below). [ "article:topic", "authorname:facciottim", "notebene:no", "showtoc:no", "glmol:yes" ], Associate Professor (Biomedical Engineering). The human respiratory system is an efficient system of inspiring and expiring respiratory gases. The amino group consists of a nitrogen atom attached by single bonds to hydrogen atoms. In this tutorial, you will find the basic structure of a neuron, the different classes of neurons, and membrane potentials. A phosphate group is a phosphorus atom covalently bound to four oxygen atoms and contains one P=O bond and three P-O− bonds. For example, look at an amino acid. Get to know how proteins are able to perform as enzymes, cofactors, or regulators. Complexation and solvation are also caused by specific interactions of functional groups. F A C E B Correct Of the choices, this is the only one that contains phosphorus. The interactive figures below (try spinning the molecules) depict the two molecules above, deoxyadenosine monophosphate and phosphoserine as three-dimensional models. A functional group is, if you like, what gives a molecule its 'character'. Functional groups binding to a central atom in a coordination complex are called ligands. But what’s on the surface of the molecules determines their chemical behavior. Two of the oxygen atoms have a negative charge. Figure 6. Each has a methyl group circled in red. Have questions or comments? An example of a nonpolar group is the methane molecule (see discussion in Bond Types Chapter for more detail). Figure 3. The carboxyl group is very versatile. A hydroxyl (alcohol group) is an -OH group covalently bonded another atom. Functional groups are what make molecules do what they do. In a polar bond or molecule, electrons will concentrate in some areas than others. Figure 5. Each has a phosphate group circled in red. These bonds are polar covalent, meaning the electron involved in forming the bonds is not shared equally between the C-O and O-H bonds. A functional group is a collection of atoms in a molecule that are responsible for the characteristic reactions of the compound. In Figure 7 are images of a nucleotide, deoxyadenosine monphosphate (left), and a phosphoserine (right). Many topics in modern biology are dependent on an understanding of Chemistry - we encourage you to explore our Chemistry playlist as well. Phosphate groups transfer energy between organic molecules. The amino acid isoleucine is on the left, and cholesterol is on the right. 0 of 4 completed. Practice: All of the following are examples of functional groups in biology except: a) -CH 3. b) -COOH. We depict some important functional groups commonly found in biological molecules above: hydroxyl, methyl, carbonyl, carboxyl, amino, sulfanyl, and phosphate. With bonds and molecules, the property we care about is usually the distribution of electrons and therefore the electric charge between the atoms. © 2001-2020 BiologyOnline. Carboxylic acid is a combination of a carbonyl group and a hydroxyl group attached to the same carbon, resulting in new characteristics. A nucleotide, deoxyadenosine monphosphate, is on the left, and phosphoserine is on the right. A functional group is a specific group of atoms within a molecule responsible for a characteristic of that molecule. Before using our website, please read our Privacy Policy. The methyl group is the only nonpolar functional group in our class list above. Hydroxyl groups appear on carbohydrates (A), on some amino acids (B), and on nucleic acids (C). The deprotonated form of this group is neutral. In this tutorial, you will also know the common metabolic pathways of biomolecules, such as glucose and other carbohydrates, fats, proteins and amino acids, and essential nutrients... Neurons generate electric signals that they pass along to the other neurons or target tissues. This results in a delocalized negative charge on the remaining oxygen atoms. When protonated, the nitrogen atom is bound to three hydrogen atoms and has a positive charge. In the common rule of thumb "like dissolves like", it is the shared or mutually well-interacting functional groups … Part B Which of these is a phosphate group? Part C Which of these is a hydroxyl… Can you identify all the carboxyl groups on the macromolecules shown above in Figure 5? The term polar describes something that has a property that is not symmetric about it — it can have different poles (more or less of something at different places). The oxygen atom is much more electronegative than either the hydrogen or the carbon, which will cause the electrons in the covalent bonds to spend more time around the oxygen than around the C or H. Therefore, the O-H and O-C bonds in the hydroxyl group will be polar covalent bonds. Once this occurs, the nitrogen atom gains a positive charge and can now take part in ionic bonds. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. These include: hydroxyl, methyl, carbonyl, carboxyl, amino, sulfanyl, and phosphate (see Figure 1). In Bis2a we will discuss the major functional groups found in biological molecules. Short set of study notes to learn about the most common Functional Groups in biochemistry. In its protonated state, it can form hydrogen bonds with other polar compounds. Phosphate groups are common in nucleic acids and on phospholipids (the term "phospho" referring to the phosphate group on the lipid). But what’s on the surface of the molecules determines their chemical behavior. Therefore, these oxygen atoms can form hydrogen bonds with nearby hydrogen atoms that also have a δ+(hydrogen atoms bound to another electronegative atom). Some organisms are comprised of only one cell whereas others have many cells that are organized into tissues, organs, and systems. Functional groups. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. Like oxygen, nitrogen is also more electronegative than both carbon and hydrogen, which results in the amino group displaying some polar character. The amine functional group can exist in a deprotonated or protonated state. c) -H 2 O. d) -NH 2. e) -OH. It is not intended to provide medical, legal, or any other professional advice. Views expressed here do not necessarily reflect those of Biology Online, its staff, or its partners. "R" represents any other atom or extension of the molecule. Chemical groups most important in the processes of life functional groups Chemicals that affect molecular function by being directly involved in chemical reactions The seven chemical groups most important in biological processes are the hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, phosphate, and methyl groups The first six groups can act as functional groups; they are also… Attribution: Marc T. Facciotti (own work adapted from previous image of unknown source). These groups play an important role in the formation of molecules like DNA, proteins, carbohydrates, and lipids. D is a phospholipid. For more information contact us at or check out our status page at In this course, we will explore topics in Biochemistry, Cell Biology, Genetics, Molecular Biology, Viruses, Evolution, Bacteria and Archaea, Protists, Plants (Botany), Fungi, Animals (Zoology), Anatomy & Physiology,Reproduction, Development, Animal Behavior, and Ecology. As we learn more about other functional groups, we will add to the list of nonpolar functional groups. Example #1: Functional Groups Example 1. Missed the LibreFest? Hydroxyl groups appear on carbohydrates (A, glucose), on some amino acids (B, Serine), and on nucleotides (C, adenosine triphosphate). Watch the recordings here on Youtube! Phosphates make the molecule of which it is a part of an anion. The carboxyl group can ionize, which means it can act as an acid and release the hydrogen atom from the hydroxyl group as a free proton (H+). Attribution: created by Marc T. Facciotti (own work). A functional group is a specific group of atoms within a molecule that is responsible for a characteristic of that molecule. In biological molecules, the carbon skeleton determines their general 3D shape. In BIS2A, we will review the major functional groups found in biological molecules. B D E A C Correct This is an amino group, NH2. Many biologically active molecules contain one or more functional groups. It defines the chemistry of the molecule in terms of what it can do. Legal. This means that methyl groups cannot form hydrogen bonds and will not interact with polar compounds such as water.