Gene is a unit of information inside a cell which controls what a living thing will be like. Genes are passed from parents to children.

Definition of Gene:

A gene is a specific segment of DNA (deoxyribonucleic acid) that contains the instructions for building and maintaining an organism. It is the fundamental unit of heredity and plays a crucial role in determining the traits and characteristics of an individual. Genes are found on chromosomes, which are thread-like structures present in the nucleus of cells.

Structure of a Gene:
- A gene consists of a specific sequence of nucleotides, which are the building blocks of DNA.
- Each nucleotide is composed of a sugar molecule (deoxyribose), a phosphate group, and one of four nitrogenous bases: adenine (A), thymine (T), cytosine (C), or guanine (G).
- The sequence of these bases forms the genetic code, which determines the specific instructions encoded within the gene.

Function of Genes:
- Genes contain the instructions for synthesizing proteins, which are essential molecules involved in various cellular processes.
- Proteins are responsible for carrying out the majority of tasks in an organism, such as enzyme catalysis, structural support, and cell signaling.
- The sequence of nucleotides within a gene determines the order in which amino acids are assembled, ultimately forming a protein with a unique structure and function.
- Different genes are responsible for the production of different proteins, and the combination of proteins produced influences the development and functioning of an organism.

Inheritance of Genes:
- Genes are inherited from parents to offspring through the process of reproduction.
- Offspring receive half of their genes from each parent, resulting in a unique combination of genetic information.
- The inheritance of genes follows specific patterns, such as dominant and recessive traits, which determine how traits are expressed in an individual.

Genes and Genetic Variation:
- Genetic variation arises from differences in the sequence of genes among individuals of a species.
- Mutations, which are changes in the DNA sequence, can lead to variations in genes.
- Genetic variation is crucial for adaptation, evolution, and the diversity of life forms on Earth.

Conclusion:
Genes are the fundamental units of heredity, containing the instructions for building and maintaining an organism. They are composed of specific sequences of nucleotides, determining the synthesis of proteins that carry out various functions in cells. Genes are inherited from parents and contribute to the genetic variation among individuals. Understanding genes and their functions is essential for comprehending the complexity of life and advancing fields such as genetics, genomics, and biotechnology.