Which macromolecules are polymers made of nucleotides

The five nitrogenous bases are classified as pyrimidines cytosine, thymine, and uracil , which have a ring structure; and purines adenine and guanine , which have a double-ring structure. RNA molecules may have up to few-thousand nucleotides and are singlestranded, whereas DNA molecules have billions of nucleotides organized in two strings of nucleotides forming a helix.

Study Questions Write your answer in a sentence form do not answer using loose words. What is a nucleic acid? What elements are nucleic acids made of? What are the monomers that make the building blocks of nucleic acids?

What are the three components of a nucleotide? List the types of nucleic acids described in the module 6. What are the functions of nucleic acid listed in the module? Nucleotides are the monomers that make up the nucleic acid polymers. Adenosine triphosphate ATP is a nucleotide that has an important function by itself. In dehydration synthesis reactions, a water molecule is formed as a result of generating a covalent bond between two monomeric components in a larger polymer.

In hydrolysis reactions, a water molecule is consumed as a result of breaking the covalent bond holding together two components of a polymer. In our bodies, food is first hydrolyzed, or broken down, into smaller molecules by catalytic enzymes in the digestive tract. This allows for easy absorption of nutrients by cells in the intestine. Each macromolecule is broken down by a specific enzyme. For instance, carbohydrates are broken down by amylase, sucrase, lactase, or maltase.

Proteins are broken down by the enzymes trypsin, pepsin, peptidase and others. Lipids are broken down by lipases. Once the smaller metabolites that result from these hydrolytic enzymezes are absorbed by cells in the body, they are further broken down by other enzymes. The breakdown of these macromolecules is an overall energy-releasing process and provides energy for cellular activities. Privacy Policy. Skip to main content. Biological Macromolecules.

Search for:. Synthesis of Biological Macromolecules. Types of Biological Macromolecules Biological macromolecules, the large molecules necessary for life, include carbohydrates, lipids, nucleic acids, and proteins. Learning Objectives Identify the four major classes of biological macromolecules. Key Takeaways Key Points Biological macromolecules are important cellular components and perform a wide array of functions necessary for the survival and growth of living organisms.

The four major classes of biological macromolecules are carbohydrates, lipids, proteins, and nucleic acids. Key Terms polymer : A relatively large molecule consisting of a chain or network of many identical or similar monomers chemically bonded to each other. Dehydration Synthesis In dehydration synthesis, monomers combine with each other via covalent bonds to form polymers. Learning Objectives Explain dehydration or condensation reactions.

Key Takeaways Key Points During dehydration synthesis, either the hydrogen of one monomer combines with the hydroxyl group of another monomer releasing a molecule of water, or two hydrogens from one monomer combine with one oxygen from the other monomer releasing a molecule of water.

The monomers that are joined via dehydration synthesis reactions share electrons and form covalent bonds with each other. As additional monomers join via multiple dehydration synthesis reactions, this chain of repeating monomers begins to form a polymer. Complex carbohydrates, nucleic acids, and proteins are all examples of polymers that are formed by dehydration synthesis.

Monomers like glucose can join together in different ways and produce a variety of polymers. Monomers like mononucleotides and amino acids join together in different sequences to produce a variety of polymers. Key Terms covalent bond : A type of chemical bond where two atoms are connected to each other by the sharing of two or more electrons.

Hydrolysis Hydrolysis reactions result in the breakdown of polymers into monomers by using a water molecule and an enzymatic catalyst. Learning Objectives Explain hydrolysis reactions.

However, fats do have important functions. Fats serve as long-term energy storage. They also provide insulation for the body. Phospholipids are the major constituent of the plasma membrane. Like fats, they are composed of fatty acid chains attached to a glycerol or similar backbone. Instead of three fatty acids attached, however, there are two fatty acids and the third carbon of the glycerol backbone is bound to a phosphate group.

The phosphate group is modified by the addition of an alcohol. A phospholipid has both hydrophobic and hydrophilic regions. The fatty acid chains are hydrophobic and exclude themselves from water, whereas the phosphate is hydrophilic and interacts with water. Cells are surrounded by a membrane, which has a bilayer of phospholipids. The fatty acids of phospholipids face inside, away from water, whereas the phosphate group can face either the outside environment or the inside of the cell, which are both aqueous.

Because fat is the most calorie dense food and having a storable, high calorie compact energy source would be important to survival. The nature of its fat also made it an important trade good. Like salmon, ooligan returns to its birth stream after years at sea. Its arrival in the early spring made it the first fresh food of the year. As you learned above all fats are hydrophobic water hating.

To isolate the fat, the fish is boiled and the floating fat skimmed off. Importantly it is a solid grease at room temperature. Because it is low in polyunsaturated fats which oxidize and spoil quickly it can be stored for later use and used as a trade item. Its composition is said to make it as healthy as olive oil, or better as it has omega 3 fatty acids that reduce risk for diabetes and stroke. It also is rich in three fat soluble vitamins A, E and K. Unlike the phospholipids and fats discussed earlier, steroids have a ring structure.

Although they do not resemble other lipids, they are grouped with them because they are also hydrophobic. All steroids have four, linked carbon rings and several of them, like cholesterol, have a short tail. Cholesterol is a steroid. Cholesterol is mainly synthesized in the liver and is the precursor of many steroid hormones, such as testosterone and estradiol. It is also the precursor of vitamins E and K. Cholesterol is the precursor of bile salts, which help in the breakdown of fats and their subsequent absorption by cells.

Although cholesterol is often spoken of in negative terms, it is necessary for the proper functioning of the body. It is a key component of the plasma membranes of animal cells. Waxes are made up of a hydrocarbon chain with an alcohol —OH group and a fatty acid. Examples of animal waxes include beeswax and lanolin. Plants also have waxes, such as the coating on their leaves, that helps prevent them from drying out.

Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective; they may serve in transport, storage, or membranes; or they may be toxins or enzymes. Each cell in a living system may contain thousands of different proteins, each with a unique function. Their structures, like their functions, vary greatly.

They are all, however, polymers of amino acids, arranged in a linear sequence. The functions of proteins are very diverse because there are 20 different chemically distinct amino acids that form long chains, and the amino acids can be in any order. For example, proteins can function as enzymes or hormones.

Enzymes , which are produced by living cells, are catalysts in biochemical reactions like digestion and are usually proteins. Each enzyme is specific for the substrate a reactant that binds to an enzyme upon which it acts.

Enzymes can function to break molecular bonds, to rearrange bonds, or to form new bonds. An example of an enzyme is salivary amylase, which breaks down amylose, a component of starch. Hormones are chemical signaling molecules, usually proteins or steroids, secreted by an endocrine gland or group of endocrine cells that act to control or regulate specific physiological processes, including growth, development, metabolism, and reproduction.

For example, insulin is a protein hormone that maintains blood glucose levels. Proteins have different shapes and molecular weights; some proteins are globular in shape whereas others are fibrous in nature.

For example, hemoglobin is a globular protein, but collagen, found in our skin, is a fibrous protein. Protein shape is critical to its function. Changes in temperature, pH, and exposure to chemicals may lead to permanent changes in the shape of the protein, leading to a loss of function or denaturation to be discussed in more detail later. All proteins are made up of different arrangements of the same 20 kinds of amino acids.

Amino acids are the monomers that make up proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom bonded to an amino group —NH 2 , a carboxyl group —COOH , and a hydrogen atom. Every amino acid also has another variable atom or group of atoms bonded to the central carbon atom known as the R group.

The R group is the only difference in structure between the 20 amino acids; otherwise, the amino acids are identical. The chemical nature of the R group determines the chemical nature of the amino acid within its protein that is, whether it is acidic, basic, polar, or nonpolar.

Each amino acid is attached to another amino acid by a covalent bond, known as a peptide bond, which is formed by a dehydration reaction.

The carboxyl group of one amino acid and the amino group of a second amino acid combine, releasing a water molecule. The resulting bond is the peptide bond. The products formed by such a linkage are called polypeptides. While the terms polypeptide and protein are sometimes used interchangeably, a polypeptide is technically a polymer of amino acids, whereas the term protein is used for a polypeptide or polypeptides that have combined together, have a distinct shape, and have a unique function.

The Evolutionary Significance of Cytochrome cCytochrome c is an important component of the molecular machinery that harvests energy from glucose. For example, scientists have determined that human cytochrome c contains amino acids. For each cytochrome c molecule that has been sequenced to date from different organisms, 37 of these amino acids appear in the same position in each cytochrome c. This indicates that all of these organisms are descended from a common ancestor.

On comparing the human and chimpanzee protein sequences, no sequence difference was found. When human and rhesus monkey sequences were compared, a single difference was found in one amino acid. In contrast, human-to-yeast comparisons show a difference in 44 amino acids, suggesting that humans and chimpanzees have a more recent common ancestor than humans and the rhesus monkey, or humans and yeast.

As discussed earlier, the shape of a protein is critical to its function. To understand how the protein gets its final shape or conformation, we need to understand the four levels of protein structure: primary, secondary, tertiary, and quaternary. The unique sequence and number of amino acids in a polypeptide chain is its primary structure.

The unique sequence for every protein is ultimately determined by the gene that encodes the protein. Any change in the gene sequence may lead to a different amino acid being added to the polypeptide chain, causing a change in protein structure and function.

What is most remarkable to consider is that a hemoglobin molecule is made up of two alpha chains and two beta chains that each consist of about amino acids. The molecule, therefore, has about amino acids. The structural difference between a normal hemoglobin molecule and a sickle cell molecule—that dramatically decreases life expectancy in the affected individuals—is a single amino acid of the This can lead to a myriad of serious health problems, such as breathlessness, dizziness, headaches, and abdominal pain for those who have this disease.

Folding patterns resulting from interactions between the non-R group portions of amino acids give rise to the secondary structure of the protein. Both structures are held in shape by hydrogen bonds.

In the alpha helix, the bonds form between every fourth amino acid and cause a twist in the amino acid chain. The R groups are attached to the carbons, and extend above and below the folds of the pleat.

The pleated segments align parallel to each other, and hydrogen bonds form between the same pairs of atoms on each of the aligned amino acids. The unique three-dimensional structure of a polypeptide is known as its tertiary structure.

This structure is caused by chemical interactions between various amino acids and regions of the polypeptide. Primarily, the interactions among R groups create the complex three-dimensional tertiary structure of a protein. There may be ionic bonds formed between R groups on different amino acids, or hydrogen bonding beyond that involved in the secondary structure.

When protein folding takes place, the hydrophobic R groups of nonpolar amino acids lay in the interior of the protein, whereas the hydrophilic R groups lay on the outside. The former types of interactions are also known as hydrophobic interactions.