Molecular Basis of Inheritance

In molecular biology, the concept of the molecular basis of inheritance refers to the mechanisms by which genetic information is stored, transmitted, and expressed in living organisms. These mechanisms involve the structure and function of DNA, as well as the processes of DNA replication, transcription, and translation.

Structure of DNA

DNA (deoxyribonucleic acid) is a double-stranded molecule that carries the genetic information in all living organisms. It consists of two polynucleotide chains that are held together by hydrogen bonds between complementary base pairs. The four bases present in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).

Replication of DNA

DNA replication is a process by which DNA makes an identical copy of itself. It occurs during the S phase of the cell cycle and is essential for cell division and the transmission of genetic information from parent to offspring. The process involves the unwinding of the DNA double helix, separation of the two strands, and the synthesis of new complementary strands using the existing strands as templates.

Transcription

Transcription is the process by which genetic information in DNA is copied into RNA (ribonucleic acid). It occurs in the cell nucleus and involves the synthesis of a single-stranded RNA molecule using one of the DNA strands as a template. The RNA molecule is complementary to the DNA template and contains the same bases as DNA, except that thymine is replaced by uracil (U).

Translation

Translation is the process by which the genetic information carried by mRNA (messenger RNA) is used to synthesize proteins. It takes place in the cytoplasm of cells on ribosomes. During translation, the mRNA is read in groups of three nucleotides called codons. Each codon specifies a particular amino acid, which is added to the growing polypeptide chain. The process continues until a stop codon is reached, signaling the end of protein synthesis.

NCERT Solutions - Chapter 6 - Molecular Basis of Inheritance, Class 12, Biology

NCERT Solutions for Chapter 6 of the Biology textbook for Class 12 provide a comprehensive understanding of the molecular basis of inheritance. The solutions cover important topics such as the structure of DNA, DNA replication, transcription, and translation. They also provide explanations for various concepts and processes involved in the molecular basis of inheritance.

By studying the NCERT solutions, students can gain a deeper insight into the molecular mechanisms underlying genetic inheritance. The solutions also include diagrams and illustrations to aid in understanding the complex processes involved.

Overall, the NCERT Solutions for Chapter 6 - Molecular Basis of Inheritance, Class 12, Biology serve as a valuable resource for students to enhance their knowledge and comprehension of the molecular basis of inheritance. They help students grasp the fundamental concepts and processes in a clear and concise manner, facilitating better understanding and retention of the subject matter.