The pyrimidine bases present in DNA are :
- cytosine and adenine
- cytosine and guanine
- cytosine and thymine
- cytosine and uracil
The Correct Option is C
Approach Solution - 1
Approach Solution -2
The nitrogenous bases that are present in DNA are purine and pyrimidine. The two pyrimidine bases present in DNA are cytosine and thymine. Pyrimidine is a heterocyclic aromatic organic compound. It is a six membered ring that contains four carbon atoms and two nitrogen atoms. Apart from cytosine and thymine, uracil is also a pyrimidine, but it is present in RNA.
Cytosine: contains an amine group and keto group at carbon-4 and carbon-2 position. Cytosine binds with guanine with a triple bond.
Thymine: contains a methyl group (CH3) in the place of the keto group that is at carbon-2. The anime group is present at carbon-4. Thymine bonds with adenine with double bond.
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Concepts Used:
Biomolecules
Biomolecules are the most essential organic molecules, which are involved in the maintenance and metabolic processes of living organisms. These non-living molecules are the actual foot-soldiers of the battle of sustenance of life.
There are four major classes of Biomolecules – Carbohydrates, Proteins, Nucleic acids and Lipids.
- Carbohydrates are chemically defined as polyhydroxy aldehydes or ketones or compounds which produce them on hydrolysis.
- Proteins are another class of indispensable biomolecules, which make up around 50per cent of the cellular dry weight. Proteins are polymers of amino acids arranged in the form of polypeptide chains. The structure of proteins is classified as primary, secondary, tertiary and quaternary in some cases.
- Nucleic acids refer to the genetic material found in the cell that carries all the hereditary information from parents to progeny. There are two types of nucleic acids namely, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The main function of nucleic acid is the transfer of genetic information and synthesis of proteins by processes known as translation and transcription.
- Lipids are organic substances that are insoluble in water, soluble in organic solvents, are related to fatty acids and are utilized by the living cell.