DNA or Deoxyribonucleic Acid is the molecular structure that contains our unique hereditary genetic codes. It is made from four predominant nitrogenous bases: Adenine, Guanine, Cytosine, and Thymine. These four building blocks are repeated repeatedly in a sequence that contains a human's genetic code. One of the most crucial features of DNA is replicating by itself. The bases are connected via solid chemical bonds.
The discovery of DNA opened up several opportunities for innovation in biology. It's a lesser-known fact that Friedrich Miescher, a Swiss Chemist, first identified DNA in the late 1860s. Furthermore, Watson, Franklin, and Crick described the structure of DNA in 1953. They also received a Nobel Prize for their discovery.
Structure of the DNA
Essentially, DNA is a nucleic acid, the structural component of all living organisms. The DNA is made of two strands twisted together to make a double helix structure. In simpler terms, it looks like a twisted ladder. Each strand of DNA is made up of units of nucleotides repeating in a pattern to form a polynucleotide chain. Each nucleotide is made of a nitrogenous base, pentose sugar, and a phosphate group. The sugar in the nucleotide is referred to as deoxyribose, from which DNA derives its name. Nucleotides are held together by a covalent bond between the sugar group of one nucleotide and the phosphate group of the other nucleotide. Thus, forming the sugar-phosphate backbone.
Function of DNA
- Replication- It is perhaps one of the central biological functions of DNA. During cellular division, a strand of the DNA replicated itself to pass on hereditary traits to the following cells. The double-helix structure will unwind itself during the division to make two separate DNA strands.
- Mutation- The next function is DNA mutation. Mutating plays a vital role in evolution. The replication process doesn't produce an accurate copy of the DNA. It allows living organisms to modify themselves or develop specific abilities that make it easier to adapt and survive during extreme situations.
- Cellular Management- Even though all cells in a living organism contain the same genetic code, it performs different functions. For instance, stomach cells produce enzymes and digestive juices. This process is referred to as cell differentiation. DNA sends signals to control the production of proteins involved during digestion.
- Encoding - DNA produces the suitable proteins to carry out the function of each cell. The DNA uses three base sections referred to as codons to control the production of proteins.
DNA can be a complicated structure to learn and understand. There are approximately 3 million base pairs present in every human. Expand your knowledge by reading up more on DNA and its components.
FAQs on DNA
Q.1. How many types of DNA tests are there?
There are mainly three kinds of DNA tests. They are- Y-chromosome or Y-DNA, autosomal and mitochondrial or mtDNA.
Q.2. What are the base pairs?
There are two base pairs units. Adenine (A) pairs up with Thymine (T), and Cytosine (C) pairs up with Guanine (G)
Q.3. Where is DNA found?
The DNA of an organism is located in the cell's nucleus, and it is called nuclear DNA. A small portion of DNA is also found in the mitochondria, called mitochondrial DNA.
Q.4. Can people share the same DNA?
Typically, humans share about 99% of DNA, and 1% makes us unique. However, identical twins are known to share the same DNA with each other.