WHAT IS GENE?
This may help.
http://kidshealth.org/kid/talk/qa/what_is_gene.html
A gene is a segment of DNA (deoxyribonucleic acid) that carries the instructions for building and functioning of one or more specific molecules in an organism. Genes are the basic units of heredity and determine many of an organism's traits, such as eye color, height, and predisposition to certain diseases. To understand what a gene is, you can follow these steps:
1. Start with the basics of genetics: Genes are part of the larger field of genetics, which is the study of heredity and the variation of inherited traits. Understanding the fundamentals of genetics will give you a good foundation to comprehend what a gene is.
2. Learn about DNA: Genes are made up of DNA, a type of molecule that carries the genetic instructions. DNA is composed of nucleotides, which are building blocks that include four different bases: adenine (A), thymine (T), cytosine (C), and guanine (G). The specific sequence of these bases in a gene determines the instructions it carries.
3. Discover the concept of gene expression: Genes are not just static pieces of DNA; they are actively involved in making proteins, which are the molecules responsible for most of the functions in our bodies. The process of gene expression involves transcribing the information in a gene into a molecule called messenger RNA (mRNA), and then translating that mRNA into a protein.
4. Explore the structure and organization of genes: Genes can be simple or complex, with different lengths and arrangements of DNA sequences. They often contain coding regions, called exons, which are the sequences that are translated into proteins. Genes also have non-coding regions, called introns, which are removed during the process of gene expression.
By understanding these fundamental concepts in genetics, you can grasp the concept of what a gene is and the role it plays in determining various traits in organisms.