DNA
The genetic material in the nucleus of a cell is composed of a chemical called Deoxyribonucleic acid. The material inside the nucleus of cells, carrying the genetic information of a living being.. DNA is a polymer, a large and complex molecule. It is made up of two strands forming a twisted ladder structure called a The shape of the DNA molecule, with two strands twisted together in a spiral.. It carries the The code formed by the order of the bases in DNA that determines an organism's characteristics., which determines the characteristics of a living Living entity, eg animals, plants or microorganisms..
Except for identical twins, each person's DNA is unique. This is why people can be identified using DNA fingerprinting. DNA can be cut up and separated, which can form a 'bar code' that is different from one person to the next.
Chromosomes
The cell's The nucleus controls what happens inside the cell. Chromosomes are structures found in the nucleus of most cells. The plural of nucleus is nuclei. contains chromosomes. These are long threads of DNA, which are made up of many genes.
Genes
A gene is a small section of DNA in a chromosome. Each gene codes for a particular sequence of amino acids in order to make a specific protein. It is the unit of heredity, and may be copied and passed on to the next generation.
The diagram shows the relationship between the cell, its nucleus, chromosomes in the nucleus, and genes.