Question

What is gene?Describe its structure and function?

Answer 1

GENE
(in informal use) a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

(in technical use) a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule which a cell (or virus) may synthesize.

Gene structure. Gene structure is the organisation of specialised sequence elements within a gene. ... Agene is transcribed (copied) from DNA into RNA, which can either be non-coding (ncRNA) with a directfunction, or an intermediate messenger (mRNA) that is then translated into protein.

FUNCTION
A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases.

Answer 2

Gene structure is the organisation of specialised sequence elements within a gene. Genes contain the information necessary for living cells to survive and reproduce.[1][2] In most organisms, genes are made of DNA, where the particular DNA sequence determines the function of the gene. A gene is transcribed (copied) from DNA into RNA, which can either be non-coding (ncRNA) with a direct function, or an intermediate messenger (mRNA) that is then translated into protein. Each of these steps is controlled by specific sequence elements, or regions, within the gene. Every gene, therefore, requires multiple sequence elements to be functional.[2] This includes the sequence that actually encodes the functional protein or ncRNA, as well as multiple regulatory sequence regions. These regions may be as short as a few base pairs, up to many thousands of base pairs long.

Much of gene structure is broadly similar between eukaryotes and prokaryotes. These common elements largely result from the shared ancestry of cellular life in organisms over 2 billion years ago.[3] Key differences in gene structure between eukaryotes and prokaryotes reflect their divergent transcription and translation machinery.[4][5]Understanding gene structure is the foundation of understanding gene annotation, expression, and function.[6]