Class XI Biotechnology (Subject Code – 045, Session 2025–26)

Section A – Unit I: Biotechnology – An Overview

This section introduces the concept of Biotechnology, its historical development, and its modern applications. Biotechnology is defined as the technological application that uses biological systems, living organisms, or their derivatives to develop useful products or processes.

The chapter explains how biotechnology evolved from traditional fermentation processes like curd, bread, wine, and beer production to modern technologies such as Recombinant DNA Technology, Cloning, Cell Culture, Protein Engineering, and Nanobiotechnology.

It also highlights applications of biotechnology in health, agriculture, chemical industries, textile industries, and environmental management.

Important Questions from Section A:

Define biotechnology.

Why is modern biotechnology considered multidisciplinary?

What is Recombinant DNA Technology?

Explain the concept of cloning. Differentiate between molecular cloning and animal cloning.

Mention two applications of biotechnology in agriculture.

Describe the steps involved in Somatic Cell Nuclear Transfer (SCNT).

Section B – Unit II: Molecules of Life

This section deals with biomolecules, the building blocks of life. It explains carbohydrates, proteins, lipids, and nucleotides in detail.

Carbohydrates are discussed in terms of monosaccharides, glycosidic bonds, reducing sugars, and Benedict’s test. The formation of ring structures (Haworth projection), alpha and beta anomers, and properties of sugars are also explained.

Proteins are built from amino acids. The structure of amino acids, peptide bond formation, Ninhydrin test, and classification of amino acids are described clearly.

Lipids such as fatty acids, phospholipids, and cholesterol are discussed along with tests like Bromine water test and Acrolein test.

Nucleotides, which are building blocks of DNA and RNA, are explained with their components: pentose sugar, nitrogenous base, and phosphate group.

Important Questions from Section B:

What are the characteristics of monosaccharides?

What are reducing sugars? Explain Benedict’s test.

What is a glycosidic bond?

Describe the Ninhydrin test. Why does proline give a different color?

Differentiate between nucleotide and nucleoside.

Compare saturated and unsaturated fatty acids.

What are the components of a nucleotide?

Section C – Unit III & IV: Genetics, Cells and Organisms

This section focuses on genetics, molecular biology, and cell biology.

It explains concepts of genetics including historical developments, DNA as genetic material, DNA replication, transcription, translation, genetic code, and mutations. Human genetic disorders are also discussed.

The section further describes cell structure, cell division, cell cycle, growth and development, nutrition, reproduction, and immune response in animals.

This unit provides a complete understanding of life from the molecular level to the cellular level.

Important Questions from Section C:

Who proved that DNA is the genetic material?

Explain the process of DNA replication.

Differentiate between transcription and translation.

What are mutations?

Describe the stages of the cell cycle.

Explain types of cell division.

What is immune response in animals?