[Biology Class Notes] on Difference Between Ribose and Deoxyribose Pdf

The nuclear material decides the physical traits of an organism. This nuclear material is made of deoxyribonucleic acid (DNA). All the biochemical reactions and physical features of an organism are decided and controlled by the DNA present in the nucleus of every cell. All living beings have their specific set of DNA giving instructions to all the cell organelles to perform their respective functions. The sequences of the DNA molecules make a DNA strand that is found in the nucleus in the form of chromosomes.

 

The prime constituent of the DNA molecules is a 5-carbon sugar molecule. It has two chemical forms that construct the DNA and RNA structures in the nucleus of every cell. In this article, we will discuss the definition and differences of these 5-carbon ribose and deoxyribose sugar molecules.

 

What is Ribose?

Ribose is a 5-carbon simple sugar. The chemical formula of this sugar molecule is H−(C=O)−(CHOH)₄−H. This is the prime component of ribonucleic acid strands. It forms ribonucleotides. These ribonucleotides are required for encoding, decoding, and regulation of the genes’ expressions. It is a monosaccharide or a simple sugar acting as the base component to form the building blocks of RNA strands.

What is Deoxyribose?

Deoxyribose, on the other hand, is a monosaccharide too. It also has the same 5-carbon formula as that of ribose sugar but loses an oxygen atom. Its chemical formula is H−(C=O)−(CH₂)−(CHOH)₃−H. It is actually derived from ribose sugar. Deoxyribose is the prime constituent of the building block of DNA molecules and DNA strands. It has an aldehyde (CHO) group attached to the molecule. Hence, it is also an aldopentose.

 

The ribose and deoxyribose structures are almost the same. Both are simple sugars but deoxyribose has one oxygen atom less in its molecular structure. It plays a major role in the formation of the DNA bases to form the double-helix structure. These double-helix DNA structures are the prime constituent of the chromosomes in the nucleus of a cell.

Difference Between Ribose and Deoxyribose

Ribose was discovered by the eminent scientist Emil Fisher in 1891. Deoxyribose was discovered by Phoebus Levene in 1921. Let us discuss the difference between Ribose and Deoxyribose.

• The chemical formula of Ribose is H−(C=O)−(CHOH)₄−H whereas Deoxyribose has the chemical formula H−(C=O)−(CH₂)−(CHOH)₃−H. As you can see, an oxygen atom is missing from the latter formula. This is the prime difference between the two monosaccharide molecules.  

• The IUPAC name of Ribose is (2S,3R,4S,5R)-5-(hydroxymethyl)oxolane-2,3,4-triol. The IUPAC name of Deoxyribose is 2-deoxy-D-ribose. It is also known as 2-deoxy-D-erythro-pentose.

• Ribose has a hydrogen atom attached to its molecule at position 2. In the same position, Deoxyribose has a hydroxyl (OH) functional group attached.

• Both of the sugar molecules develop the blueprint of an organism. The biochemical functioning and physiological traits are developed by DNA and RNA. RNA is formed by Ribose and other components whereas DNA is formed by Deoxyribose and other components.

• RNA is single-stranded gene material whereas DNA is double-stranded.

• The molar mass of ribose is 150.13 g/mol. The molar mass of Deoxyribose is 134.13 g/mol. The difference in the molar masses is 16 due to the absence of one oxygen atom in the structure of Deoxyribose.

• DNA is the prime source of genetic information that regulates enzymatic activities at the cellular level.

• Ribose combines with nitrogenous bases such as adenine, guanine, cytosine, and uracil to form ribonucleosides. A phosphate group then attaches to the ribonucleoside to form a ribonucleotide. Deoxyribose, on the other hand, forms deoxyribonucleotides by combining with adenine, guanine, thiamine, and cytosine.
  

Now that you have understood the difference between ribose and deoxyribose sugar in terms of their chemical structure and functions, you can easily prepare the chapter well. The structural difference can be cleared if you follow the chemical formula and study the structure elaborately. Learn about both the monosaccharide molecules so that you can understand how they differ functionally. 

 

Ribose and Deoxyribose are both very important topics to cover and cover good weightage in exams as many questions can be derived from both these topics. Also, both the topics are directly related to the living organisms and the cells found within them, together these both form the backbone of the genetic information which is being transferred continuously from years from the ancestors to the present day generation or organisms as they comprise of very important hereditary information like the shape, functions etc. in the living organisms. 

For example, the working application of DNA in a human body can be understood as the child has somewhat similar physical features in its body which seem to become more common with time to its parent’s physical body features like the nose, eyes etc. Also, the child can inherit genetic diseases which their parents or ancestors might have and is passed on to them like low eyesight, sugar, HIV etc. 

Relation between Ribose and Deoxyribose 

Ribose and its closely related compound which is deoxyribose are stated as the main building blocks or the backbone in the formation of chains in nucleic acids, which are commonly and more often known by the term DNA (Deoxyribonucleic acid) and RNA (Ribonucleic acid). Ribose is used in RNA in the form of sugar and deoxyribose is used in DNA as a means of sugar. Deoxyribose and Ribose, both of them have been classified under monosaccharides, aldoses, pentoses, and are known for their property of reducing sugars.

One more thing that is common in Ribose and Deoxyribose is that they both contain a pentose sugar in them where DNA is deoxyribose. One of the most foundational and important similarities between DNA and RNA is that both of them consist of phosphate as their backbone in the structure to which their foundations are connected. 

Structural Difference between Ribose and Deoxyribose

Ribose the structure looks more like a chair and has a similar pattern just like that of glucose but with one exception which is, that ribose has a functional group of aldehyde and the ring closure occurs at carbon position 1 which is similar to that in glucose, the only exception here is that ribose is a pentose with five carbons in it which leads to the formation of a structure with five members or a five-membered ring. 

Whereas in the structure of deoxyribose it can exist as a linear molecule or in the form of a five or six-membered ring. Deoxyribose is also known as an aldopentose because it contains a group of carbonyl at the end of the molecule. The substitution of a group of phosphate and a nucleic acid-base on this ring allows deoxyribose to function as the main support or the backbone of DNA.