Biomolecules

Types of Biomolecules

Biomolecules are needed by the body to perform different life processes. The types of biomolecules include proteins, carbohydrates, lipids, nucleic acids, vitamins, and minerals. Carbohydrates and lipids are available for energy production and storage, while nucleic acids( DNA and RNA) carry genetic material. For exams, the functions of biomolecules are a key focus area. The various types of biomolecules are listed below:

Carbohydrates: Types and Functions

Carbohydrates are organic molecules made of carbon, hydrogen, and oxygen in a 2:1 ratio. They may be simple sugars or complex polysaccharides.

• Simple carbohydrates: glucose, a quick energy source

• Complex carbohydrates: starch, cellulose, long‑term energy and structure

Carbohydrates are responsible for providing energy and also help in building the cell walls of the cell. They are crucial in NEET Biology Notes and often appear in NEET MCQs.

Types of Carbohydrates

Different types of carbohydrates are discussed below:

Functions of Carbohydrates

Some of the major functions of carbohydrates are discussed below in the table:

Proteins: Types and Roles

Proteins are large biomoleculesmade of amino acids. Amino acids join by peptide bonds to form complex structures. Proteins are essential in NEET Biology Notes and Class 11 Biology Notes because they perform multiple roles in the body.

Proteins build body structure and speed up the reactions taking place in different processes. They act as catalysts and are responsible for determining the shape of how they work. Sometimes they also work as enzymes. Protein is also known as an amino acid polymer because it is made up of organic compounds. There are 20 types of amino acids, each contributing to protein diversity.

Types of Proteins

Some major types of protein and their structure and composition are discussed below:

Functions of Protein

Protein is involved in enzymatic activities, as hormones, in the structure and shape of the cells, and acts in immune defence too. Some major functions are discussed below in the table:

Lipids: Types and Functions

Lipids are compounds soluble in nonpolar solvents and contain a large number of carbon-hydrogen atoms. Lipids are responsible for storing fats and oils. It is also important because it is a form of energy storage. It forms the cell membrane of the cell. Lipids are also important for processes like sending signals from one cell to another. They are generally insoluble and can be both saturated and unsaturated fats.

Types of Lipids

Triglycerides act as energy storage or fat, phospholipids are part of cell membranes, and steroids include cholesterol, which is a hormone.

Functions of Lipids

Lipids are involved in energy storage, determination of membrane fluidity plays a role in signal transduction. Some of the major functions of lipids are discussed below:

Nucleic Acids: DNA, RNA, and Nucleotides

Nucleic acids are large biomolecules that are made up of a chain of nucleotides. A nucleotide is a molecule that has a sugar, a phosphate group and a nitrogenous base. Nucleic acids are responsible for storing genetic information. DNA and RNA are made up of nucleotides and are two of the best compounds to carry genetic information. DNA carries long-term genetic data, while RNA helps the formation of different types of proteins in the body.

Types of Nucleic Acids

Major types of nucleic acids are discussed below in the table:

Functions of Nucleic Acids

Nucleic acids are involved in the replication of genetic data, and also in the synthesis of proteins, and the transmission of heredity. Some major ones are discussed below in the table:

Types of Vitamins and Coenzymes: Examples and Functions

Vitamins and coenzymes are small organic molecules that assist enzymes in biochemical reactions. They speed up metabolism and regulate essential processes in the body. In NEET Biology Notes and Class 11 Biology Notes, this topic is important because many exam questions focus on the functions of biomolecules and their role in health.

Types of Vitamins and Coenzymes

Some of the major types of vitamins and coenzymes are discussed below:

Functions of Vitamins and Coenzymes

Some of the major functions of vitamins and coenzymes are discussed below in the table:

Examples of Vitamins and Coenzymes

Examples of Vitamins: Vitamin A (retinol), Vitamin C (ascorbic acid), Vitamin D, Vitamin E, Vitamin K, and B-complex vitamins such as B₁ (thiamine), B₂ (riboflavin), B₃ (niacin).

Examples of Coenzymes: NAD⁺ (derived from niacin), FAD (derived from riboflavin), Coenzyme A (derived from pantothenic acid), and TPP (derived from thiamine).

Functions of Biomolecules NEET Biology

Biomolecules NEET Notes explain how biomolecules sustain life. In Class 11 Biology Notes, the functions of biomolecules are a high‑weightage topic and are often asked in NEET MCQs. Biomolecules are of two types.

• Structural molecules: Proteins, carbohydrates, and lipids provide energy, build tissues, and form membranes.

• Informational molecules: DNA and RNA store and transmit genetic data. Enzymes, made of proteins, act as catalysts in metabolism. Vitamins and coenzymes regulate enzyme activity and maintain homeostasis.

Understanding the functions of biomolecules like energy storage, catalysis, heredity, and regulation is important. Some important functions of Biomolecules are discussed below:

Metabolism: Anabolism vs Catabolism in Biomolecules

Metabolism is the sum of all chemical reactions in living organisms. It includes two opposite pathways: anabolism and catabolism. Both pathways work together to support growth, repair, energy supply, and balance in the body. Understanding anabolism vs catabolism in biomolecules is important for exams like NEET Biology and Class 11 Biology Notes. The synthesis and breakdown of biomolecules includes following pathways:

1. Anabolic Pathways

In anabolism, small and simpler molecules are converted into large and complex molecules, requiring energy input.

Examples: Amino acids from keratin, glucose molecules form glycogen and starch

2. Catabolic Pathways

In catabolism, large complex molecules are degraded into smaller, simpler molecules.

Examples: Protein is broken down into amino acids, and lipids are broken down into fatty acids

These two pathways are essential for total metabolism in an organism. The difference between the two is given in the table below:

Metabolic Pathways Examples

Major examples of Metabolic Pathways are discussed below in the table:

Role of Biomolecules in Health

Biomolecules are vital for maintaining human health. They regulate metabolism and support homeostasis in the human body. Biomolecules are involved in the regulation of physiological processes leading to a complex organism’s homeostasis and health condition.

• Carbohydrates supply quick energy for cellular processes.

• Proteins build tissues and act as enzymes for reactions.

• Lipids form cell membranes and store long‑term energy.

• Nucleic acids store and transmit hereditary information.

Biomolecules in Health and Disease - NEET Notes

Biomolecules are central to human health and disease. They regulate metabolism, maintain homeostasis, and support vital functions. Disorders in biomolecule metabolism, such as diabetes, hypercholesterolemia, and PKU, affect energy balance and overall health. Targeting biomolecules with therapies like insulin, statins, and enzyme replacement is key in modern medicine.

Disorders Related to Biomolecule Metabolism

Some common disorders related to biomolecule metabolism are:

Biomolecules as Therapeutic Targets

Biomolecules play a central role in the process of finding therapeutic approaches. Strategies that aim at particular biomolecules alter diseases:

• Insulin therapy for diabetes regulates blood glucose.

• Statins lower cholesterol in hypercholesterolemia.

• Enzyme replacement therapy treats PKU by restoring metabolic function.

Advances in biotechnology and pharmacology continue to develop new biomolecular therapies, improving patient outcomes and health management.

Enzymes and Biomolecules

Enzymes are proteins that control the speed of metabolic reactions. They help in both biosynthesis and degradation of biomolecules. Enzymes lower the activation energy and make reactions faster. Catalytic actions of enzymes are involved in biosynthesis as well as the degradation of biomolecules. In NEET Biology Notes and Class 11 Biology Notes, enzymes are often linked with the functions of biomolecules and appear in NEET MCQs.

For example:

• Specific enzymes of DNA polymerase are used to synthesise DNA

• Proteases are used to deconstruct proteins into amino acids.

Biomolecules NEET MCQs (With Answers & Explanations)

Important topics in the chapter Biomolecules are the

• Types of Biomolecules (Proteins, Carbohydrates, Lipids, Nucleic Acids)

• Functions of Biomolecules

• Biomolecules in Health and Diseases

• Enzymes

Practice Questions for NEET

Q1. The cellular pool comprises hundreds of organic and inorganic biomolecules. The organic molecules include

1. Carbohydrates

2. Proteins

3. Nucleic acids

4. More than one option correct

Correct answer: 4) More than one option correct

Explanation:

The organic molecules present within the cell are categorized into:

1. Carbohydrates:
- Monosaccharides (e.g., glucose) are simple sugars serving as energy sources.
- Polysaccharides (e.g., starch, glycogen) are complex carbohydrates providing both energy and structural support to cells.

2. Proteins:
- Composed of amino acids, proteins are fundamental to various cellular activities such as enzyme function, structural integrity, signal transmission, and material transport.

3. Lipids:
- This group encompasses fats, phospholipids, and steroids which are crucial for energy storage, maintaining cell membrane structure, and participating in signaling pathways.

4. Nucleic Acids:
- DNA and RNA are the genetic material, essential for storing, transferring, and synthesizing proteins according to genetic instructions.

Hence, the correct answer is option 4) More than one option is correct.

Q2. Organic molecules contain

1. Nitrogen

2. Sulphur

3. Oxygen

4. Zinc

Correct answer: 3) Oxygen

Explanation:

Biomolecules are organic compounds essential to life, composed primarily of carbon (C), hydrogen (H), and oxygen (O). These molecules form the structural and functional basis of living organisms. In addition to these elements, some biomolecules may also contain nitrogen (N), phosphorus (P), sulfur (S), and other trace elements.

Hence, the correct answer is option 3) Oxygen.

Q3. Lecithin, a small molecular weight organic compound found in living tissues, is an example of:

1. Amino acids

2. Phospholipids

3. Glycerides

4. Carbohydrates

Correct answer: 2) Phospholipids

Explanation:

Some lipids have phosphorus and a phosphorylated organic compound in them. These are phospholipids. They are found in cell membranes. Lecithin is one example.

Option (3) is incorrect, as glycerides are another group of lipids in which both glycerol and fatty acids are present.

Option (1) and (4) are incorrect as amino acids and carbohydrates are separate groups of biomolecules.

Hence, The correct answer is option 2) Phospholipids.

Also Read:

• MCQs on Biomolecules

• Factors Affecting Enzyme Activity

• Beriberi

Recommended Video on Biomolecules