(b)++DNA+Structure+(Q+4-9)

Chromosomes are largely made out of deoxyribonucleic acid (or DNA), which is the nucleic acid that contains the unique genetic information and heredity material in all individual living organisms.
 * DNA Structures **
 * Definition (What is a DNA?) **

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This video explains what a DNA is in more detail whilst allowing you to have a brief introduction to topics that will be covered in more detail later on in the page.

The DNA controls the production of proteins that make up characteristic (or traits). This is displayed in the diagrams below:
 * Role/ Function: **

A DNA molecule is in a shape of a twisted ladder, consisting of two strands that are twisted to one another in a spiral anti-parallel manner. This shape is called the **double helix**. The backbone of the DNA (otherwise known as the two outer strands) are made up of phosphates and a sugar (of the deoxirybose group, as seen in the name deoxyribonucleic). The steps of this ladder, otherwise known as the bases of the double helix are composed of four different nucleotide molecules:
 * Structure **
 * Adenine (A)
 * Thymine (T)
 * Guanine (G)
 * Cytosine (C)



These bases always comes in pairs, known as base pairs with the following compulsory combination:
 * Adenine with Thymine
 * Guanine with Cytosine

// DNA fingerprinting in laboratories require the following steps: // DNA structure are needed as we need to figure and compare differences of each individually based on their DNA.
 * **// Isolation //**// - When the DNA is recovered from cells or tissues within the body. The sample of DNA can come from small amounts of tissue such as blood, hair, saliva or skin. //
 * **// Separation //**// - The DNA pieces are then sorted by size through a process called electrophoresis, in which the pieces are passed through a special gel made of seaweed agarose (which is a jelly-like substance produced by seaweed), to determine the size of each DNA piece. //
 * **// Profile Comparisons //**// - Researchers are then able to read and compare different DNA fingerprints to each other for matches. //

[|Here] is a link to a more detailed diagram on DNA structure.


 * Watch this video to see the structure of DNA: **

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