Login with Facebook

The Structure and Function of Macromolecules

The term macromolecules refer to molecules with a high molecular mass (greater than 1000 Uma). The dimensions of the macromolecules are extremely varied and depend on the number and nature of the component atoms; you can get to the size of the order of 100 Å (Angstrom), that is, the size of the colloidal particles. Macromolecules can be of both artificial and natural origin. Examples of artificial macromolecules are some types of polymers such as nylon 6.6, polystyrene, and polypropylene. Examples of natural macromolecules are proteins, carbohydrates, starch, lipids, cellulose, DNA and RNA, and, in general, all nucleic acids.

Macromolecules are only single large molecules. Therefore, polymers notoriously formed from smaller molecules known by the term monomers should not be included among them. Polymers (artificial macromolecules) are formed by the repetition of numerous structural units (constitutional repeating unit); the starting units, with which the polymer is formed, are called monomers, and the reaction that joins the monomers together to make up the polymer is called polymerization. An example of a polymerization reaction is that which leads to the formation of polyethylene.

As can be seen from the above case, the polymers are usually represented by indicating the CRU, without specifying the type of end groups of the chains. The monomer of polyethylene is ethylene (H2C = CH2).

An example of a natural macromolecule

An example of a natural macromolecule is cellulose. It has a chemical formula (C6H10O5) n.

 The most important chemical bond of cellulose is the 1, 4-ß-glucosidic bonds used to join the glucose units together.

Cellulose is insoluble in water and has an important structural function in plants. The wood contains about 50% of cellulose, and the cotton fibers are practically made of pure cellulose.

Constituent units of macromolecules.

 Most synthetic or natural macromolecules can be obtained by addition or condensation reactions. In the first case, the rearrangement of the chemical bonds in the monomer molecule leaves two values ​​free, which allow the linkage with other monomers without the elimination of atoms. In the condensation reaction, the monomer, which has two functional groups, can react with another monomer with the elimination of a small molecule, often of water. The building blocks of some macromolecules, both synthetic and natural, are described below; the examination has only an example purpose, to allow the reader to more easily follow the exposition of the structural aspects.

Types of Macromolecules

- Carbohydrates

- Proteins

- Lipids



Carbohydrates are mostly ternary compounds because their molecules are made up of three types of atoms, i.e., carbon C, hydrogen H, and oxygen O. The main carbohydrates are divided into monosaccharides, disaccharides, and polysaccharides. Small molecules constitute the monosaccharides or simple sugars. They are divided into pentose monosaccharides and hexose monosaccharides. Pentose monosaccharides are made up of 5 carbon atoms, and the most important is deoxyribose C5H1005 (which forms DNA) and ribose C5H1004 (which forms RNA). The hexose monosaccharides are glucose, fructose, and galactose, all having brute formula C6H1206. However, these compounds differ in the structural formula. The three hexoses are, therefore, isomers. The disaccharidethey are formed by two monosaccharide molecules joined together by a condensation reaction: 

2C6H1206 ---> C12H22011 + H20 

The most common disaccharides have the formula C12H22011 and are sucrose (glucose and fructose), maltose (two glucose molecules), and lactose (glucose and galactose). The polysaccharides consist of several monosaccharides linked together by means of a polycondensation reaction. The most important with reserve functions are starch and glycogen. Starch is a reserve molecule characteristic of plants, while glycogen is the reserve polysaccharide of animal cells. In cellulose, monomers are bound together with a different bond than that found in starch and glycogen. It is a polymer with a structural function, characteristic of the plant cell wall.


Lipids are divided into triglycerides, phospholipids, and steroids. They are ternary compounds because their molecules are made up of three types of atoms: carbon C, hydrogen H, and oxygen O. They are insoluble in water and soluble instead in organic compounds such as benzene, ether, and chloroform. Lipids are made up of glycerol, and fatty acids joined together through an esterification reaction. The glycerol (or glycerine) is a molecule is an alcohol that has three -OH groups. The fatty acids are molecules consisting of a linear hydrocarbon chain (R), which carries a carboxylic -COOH group at one end. That is, they are long-chain organic acids. Fatty acids can be saturated if only simple bonds are present between the carbon atoms in the chain, monounsaturated if there is a double bond, and polyunsaturated if there are two or more double bonds. The triglycerides are lipids formed by the union of three molecules of fatty acids with glycerol according to an esterification reaction, which gives the triglyceride and three water molecules. Triglycerides are the main form of energy storage in animal cells; they are a source of metabolic water and allow thermal insulation through subcutaneous deposits. The phospholipids are made up of a glycerol molecule combined with a phosphate group and two fatty acids. The phospholipid part of the molecule is called the polar head, while the two hydrocarbon chains of fatty acids are called apolar tails. 


Proteins are the most common macromolecules in living cells. Quaternary compounds are formed from carbon C, hydrogen H, oxygen O, and nitrogen N. Proteins are polymers made up of monomers, and amino acids.

Amino acids are organic compounds made up of a carboxylic group and an amino group. These two groups are linked together by alpha carbon and differ in group R. The amino acids present in nature are 20, of which 12 that man can synthesize and 8 essential, that is, the cells cannot synthesize them and are inserted through the diet. 

The structure of proteins 

In most proteins, different levels of the organization are recognized, coexisting in the same protein molecule. They are generally determined by each other. Thus, the primary structure determines the secondary structure and the latter, the tertiary. Functional specialization depends on the final form taken by the protein. Each protein has a precise number and sequence of amino acids. This sequence is called the primary structure. The secondary structure is found as an alpha helix, tight spiral winding of the polypeptide chain, or beta lamina, plus traits of parallel polypeptide chains. The tertiary structure assumes a compact and globular shape and is the result of folding the secondary structure on itself (folding). Sometimes two or more globular proteins associate, giving rise to the quaternary structure.


DNA is the genetic material of cells and is located in the nucleus of eukaryotic cells and in the cytoplasm of prokaryotic cells. DNA is made up of two spiral wound strands that form the “double helix.” Each filament is a polymer made up of monomers called nucleotides. Each nucleotide is made up of three basic molecules:

- a phosphate group 

- a pentose sugar deoxyribose 

- a nitrogenous base (adenine, thymine, cytosine, guanine)

Each strand of DNA is a polynucleotide and is joined to the other strand by hydrogen bonds. These bonds are established between the complementary nitrogen base pairs (adenine and thymine; cytosine and guanine) AT, CG, TA, and GC. The nitrogen bases are divided into purines (Adenine and Guanine) and pyrimidines (Thymine and Cytosine), and a purine is always bound with a pyrimidine.


RNA is a macromolecule whose monomers are the ribonucleotides consisting of a phosphate group. 

- One pentose sugar ribose a nitrogenous base (adenine, uracil, cytosine, guanine). 

RNA is made up of a single strand, i.e., a single nucleotide chain held together by phosphoester bonds. RNA is found in the cytoplasm of eukaryotic and prokaryotic cells. RNA plays a fundamental role in the process that determines the union of the various amino acids to form proteins. There are three types of RNA in cells, with different structures and functionsMacromolecule cellulose, which interact with each other and collaborate in protein synthesis.


Send Comment

Need a custom

We will write it for you.
Order now

Free Essay Examples

Free essays:

An ultimate guide about biochemical reactions
Analysis methods of Transport through biological membranes
A Comprehensive Introduction to the Mona Lisa
An ultimate guide about Biomaterials
Big data analysis in evolutionary biology
Brain-Computer Interface systems with EEG signals
Biochemistry of neurotransmitter
Bipolar disorder: Symptoms, causes, diagnosis and treatment
Cellular excitability
Characterization of biological tissues, biomaterials
Characteristics of the byzantine architecture
Commonly Confused Words: Part 2
Dynamic Systems Modeling with Machine Learning
Digital Imaging: What Is It?
Different forms of dance you should know about
Data Science: Fundamental tools for data analysis
Everything you need to know about enzymatic kinetics
Electromagnetic exposure effects on human organs
Effects of Different Environmental Factors on Artworks
Entrepreneur trends to know about
Famous Ballet Forms
Four postulates of natural selection
Famous African American literature authors
Film styles and the types of styles for shooting a film
Importance of online journalism
Importance of 3d Modelling in Architecture
Introduction to Utilitarianism
Identity theft: what to do?
Kinetic models in biology and Related fields
Know about the different forms of traditional African dances
Know about the history of science
Latest technology trends
Mass transport in a biological system
Major themes in ancient Egyptian art
Major healthcare trends
Misconceptions About the Word “Introvert”
Nonlinear Dynamics in Biology & Biomedicine
NLS (Nonlinear System) - Revolutionary system in diagnostic medicine and therapy
Neural networks: what they are and what they are for
Nuclear fusion: What it is and how it works?
Role of Homeostasis in Human Physiology
Role of a digital artist
Role of gender studies
Risk management, meaning, and importance for companies
Systems biology - An understanding the functioning of biological systems
Self-assembly for biological systems
School of American Ballet
Schizophrenia - a rare psychiatric illness | Essay
The impact of the technological innovations in medicine
The Defense mechanisms against infections
Tips for writing a great thesis statement
The Modeling of Biological Systems
Understand the importance of investigative journalism
Urban planning in the US
Understanding the sociology of Race & Ethnicity
Various theoretical perspectives of sociology
Women empowerment in modern generation
What Makes a Good Leader
What is biopolymers?
What is the cytoplasm and its function?
4 Facts about Origin of Mathematics!
5 techniques to create an animation
13 Best colleges for political science in the world
3d Model Of Building
All you need to know about the ACA Code of ethics
Architecture and Democracy: An Introduction
Architecture and Democracy: Democratic Values
Architecture and Democracy: Democratic Procedures
All You Need to Know About a Synthesis Essay
An essential guide to understanding Film Theory
Application of Artificial Intelligence in Cyber Security
Applications of electrical engineering
Augmented reality: what it is, how it works, examples
Advantages And Disadvantages Of Social Networking
All you need to know about Cryptography
Applications of astrophysical science
All you need to know about architecture engineering
Applications of geological engineering
Artificial intelligence and medicine: an increasingly close relationship
An insight into Computational Biology
ACA code of conduct
A Rose for Emily
Applications of Mathematics in daily life
Architecture mistakes to avoid
All you need to know about Toxicology
All you need to know about Holistic Medicine
All you need to know about linguistics
An introduction to Linguistics and its subfields
All you need to know about Anxiety disorder
All you need to know about Drones
A Brief Insight into Political Science
Assumptions related to feminism
All you need to know about Byzantine emperors
All you need to know about labour economics
An insight into xenobots -the first-ever robots
An ultimate guide about Biomaterials
A Comprehensive Introduction to the Mona Lisa
Analysis methods of Transport through biological membranes
An ultimate guide about biochemical reactions
How to Write a Personal Essay
Housing Needs in America
How to Write a Description Essay
How to Create an Excellent Scholarship Essay?
How to write a cause and effect essay
How to Hire the Best Essay Writing Service Provider?
How to Write a College Application Essay?
How to get the most out of your English lectures
How to write Expository Essay
How to succeed in your psychology class?
How to Write an Academic Essay in the Shortest Time?
History of Journalism
How Different Sectors are Using Artificial intelligence (AI)
How to write an informative essay
How to deliver persuasive essays?
How to Give a Convincing Presentation
How to write an essay on leadership?
Historical Art Still Around Today
Humanoid robot: what it is, how it works and price
History of Chemistry
Healthcare Advanced Computer Power: Robotics, Medical Imaging, and More
Healthcare AI: Game Changers for Medical Decision-Making and Remote Patient Monitoring
How to understand different types of English
How to Cope with Chronic Pain
How African American choreographers and dancers have influenced American dance
How mobile robot can do in logistics or in production
How To Become a Successful Entrepreneur
History of the Philosophy of Feminism
How is the climate changing?
How to Track Your Content Marketing ROI
How to Gun control In the USA?
Historical and contemporary role of labour in the modern world
How breast cancers are classified?
How the cells of our body communicate?
How the Lymphatic System Works?
How Digestive System Works
How to complete your capstone projects effectively?
How to write a research project
Healthcare technologies that help patients with better self-management
How to choose the topic of the senior capstone project