Structure and Function of Nucleic Acids
By:
Jussara Anselmo Rodrigues
Unit 11 – Assignment A
Submitted on: 14/02/2023
To: Ibikunle Idowu
Total word count 7379
, Introduction
During this report there will be the illustration of my understanding on the nucleic
acids, mainly DNA [deoxyribonucleic acid] and RNA [ribonucleic acid], the ones that
carry genetic information. DNA is a well-known double helix structure that allows
information to be copied and passed on to next generation. I will also discuss how
DNA is copied into RNA by transcription and translated into protein by translation, as
well as the impact of errors in the stages of protein synthesis.
Nucleotides
Nucleotides share a great importance to living organisms as they are the building
blocks of nucleic acids. The natural biopolymers known as nucleic acids are
recognised for storing, encoding, transmitting and expressing genetic information,
meaning they are the main substances that control all hereditary characteristics.
Each nucleotide consists of nitrogen-containing base which is attached to a pentose,
a five-carbon sugar, which is also attached to phosphate group. There are two main
types of nucleic acids are DNA and RNA. There are five possible nitrogen-containing
bases such as adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U),
and each nucleic acid has four of the five. DNA consists of A-T and G-C pairing and
RNA consists of A-U and G-C pairing, where the T is replaced with U. The nitrogen-
containing bases of nearly all nucleotides are derivatives of three heterocyclic
compounds: pyrimidine, purine and pyridine. A and G are grouped as purines and
the other three, T, C, and U are classified pyrimidines, and pyridine can be
adenosine monophosphate (AMP) and nicotinamide mononucleotide (NMN) [1]. In
contrast to nucleotides, which include a phosphate group, nucleosides do not. Rarely
do nucleosides take role in cellular metabolism [2].
The pentose sugar in DNA [2'-deoxyribose] and the sugar in RNA [ribose] are
different because they lack the hydroxyl group [-OH] on the 2’ carbon of the sugar
ring. The sugar that is joined to one of the bases is referred to as a nucleoside if it
does not have an associated phosphate group. By creating a bridge between the
sugar 5’-hydroxyl group and the subsequent sugar 3’-hydroxyl group, the phosphate
group connects the chain of sugar residues. In both RNA and DNA, these nucleoside
connections are known as phosphodiester bonds [1].
, Figure 1: Structure of nucleotide and nitrogen-containing bases. A and G consist of two rings in
their structure while A, C and U consist of one ring in their structure.
Deoxyribonucleic acid [DNA]
One of the most crucial molecules in living cells is DNA since it contains the
instructions for life. The mitochondrial genome and the 23 pairs of chromosomes
present in the human nucleus are both included in the term "genome," which refers
to an organism's whole collection of DNA molecules. For healthy growth and to
sustain life, a diploid genome must be full and functional [3]. DNA is the perfect
genetic material because of its structure and the molecule’s chemical stability.
In DNA structure, four nucleotides– A, T, C and G – are linked together to form this
polymer made of monomeric units (nucleotides), which has a backbone made up of
alternate phosphate and deoxyribose sugar residues. DNA has a double helix
structure, has two strands which run in opposite directions. The deoxyribose ring
contains carbon atoms numbered 1’ to 5’. The nitrogenous base is attached to the 1’
carbon and the phosphate is bonded to the 5’ carbon inside the monomer. This is
known as an N-glycosidic bond. The regular structure of the double helix is due to
the fact that the distance between the 1’ carbon of one strand and the opposite
strand is always the same, despite the base pair. As a result, the two sugar-
phosphate backbones are not evenly spaced along the helical axis, resulting in major
and minor grooves [3,5]. Each strand has a 5’ and a 3’ end. DNA twists as a result of
interactions between the water molecules and the components that make up DNA.
The nitrogenous bases that make up the twisting staircase are held together by
hydrogen bons. A-T and G-C do not have a strong attraction to water since they are
hydrophobic. Since cells' cytoplasm and cytosol are made up of water-based liquids,
nitrogenous bases prefer to avoid interacting with these fluids. Because the
molecules of sugar and phosphate are hydrophilic, they are attracted to water
strongly. The molecule twists to close the opening between the phosphate and sugar
strands and the nitrogenous bases, further preventing the nitrogenous bases from
By:
Jussara Anselmo Rodrigues
Unit 11 – Assignment A
Submitted on: 14/02/2023
To: Ibikunle Idowu
Total word count 7379
, Introduction
During this report there will be the illustration of my understanding on the nucleic
acids, mainly DNA [deoxyribonucleic acid] and RNA [ribonucleic acid], the ones that
carry genetic information. DNA is a well-known double helix structure that allows
information to be copied and passed on to next generation. I will also discuss how
DNA is copied into RNA by transcription and translated into protein by translation, as
well as the impact of errors in the stages of protein synthesis.
Nucleotides
Nucleotides share a great importance to living organisms as they are the building
blocks of nucleic acids. The natural biopolymers known as nucleic acids are
recognised for storing, encoding, transmitting and expressing genetic information,
meaning they are the main substances that control all hereditary characteristics.
Each nucleotide consists of nitrogen-containing base which is attached to a pentose,
a five-carbon sugar, which is also attached to phosphate group. There are two main
types of nucleic acids are DNA and RNA. There are five possible nitrogen-containing
bases such as adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U),
and each nucleic acid has four of the five. DNA consists of A-T and G-C pairing and
RNA consists of A-U and G-C pairing, where the T is replaced with U. The nitrogen-
containing bases of nearly all nucleotides are derivatives of three heterocyclic
compounds: pyrimidine, purine and pyridine. A and G are grouped as purines and
the other three, T, C, and U are classified pyrimidines, and pyridine can be
adenosine monophosphate (AMP) and nicotinamide mononucleotide (NMN) [1]. In
contrast to nucleotides, which include a phosphate group, nucleosides do not. Rarely
do nucleosides take role in cellular metabolism [2].
The pentose sugar in DNA [2'-deoxyribose] and the sugar in RNA [ribose] are
different because they lack the hydroxyl group [-OH] on the 2’ carbon of the sugar
ring. The sugar that is joined to one of the bases is referred to as a nucleoside if it
does not have an associated phosphate group. By creating a bridge between the
sugar 5’-hydroxyl group and the subsequent sugar 3’-hydroxyl group, the phosphate
group connects the chain of sugar residues. In both RNA and DNA, these nucleoside
connections are known as phosphodiester bonds [1].
, Figure 1: Structure of nucleotide and nitrogen-containing bases. A and G consist of two rings in
their structure while A, C and U consist of one ring in their structure.
Deoxyribonucleic acid [DNA]
One of the most crucial molecules in living cells is DNA since it contains the
instructions for life. The mitochondrial genome and the 23 pairs of chromosomes
present in the human nucleus are both included in the term "genome," which refers
to an organism's whole collection of DNA molecules. For healthy growth and to
sustain life, a diploid genome must be full and functional [3]. DNA is the perfect
genetic material because of its structure and the molecule’s chemical stability.
In DNA structure, four nucleotides– A, T, C and G – are linked together to form this
polymer made of monomeric units (nucleotides), which has a backbone made up of
alternate phosphate and deoxyribose sugar residues. DNA has a double helix
structure, has two strands which run in opposite directions. The deoxyribose ring
contains carbon atoms numbered 1’ to 5’. The nitrogenous base is attached to the 1’
carbon and the phosphate is bonded to the 5’ carbon inside the monomer. This is
known as an N-glycosidic bond. The regular structure of the double helix is due to
the fact that the distance between the 1’ carbon of one strand and the opposite
strand is always the same, despite the base pair. As a result, the two sugar-
phosphate backbones are not evenly spaced along the helical axis, resulting in major
and minor grooves [3,5]. Each strand has a 5’ and a 3’ end. DNA twists as a result of
interactions between the water molecules and the components that make up DNA.
The nitrogenous bases that make up the twisting staircase are held together by
hydrogen bons. A-T and G-C do not have a strong attraction to water since they are
hydrophobic. Since cells' cytoplasm and cytosol are made up of water-based liquids,
nitrogenous bases prefer to avoid interacting with these fluids. Because the
molecules of sugar and phosphate are hydrophilic, they are attracted to water
strongly. The molecule twists to close the opening between the phosphate and sugar
strands and the nitrogenous bases, further preventing the nitrogenous bases from
