Nucleic acids are macromolecules that are essential to all living organisms. They are made up of building blocks called nucleotides, which consist of a nitrogenous base, a sugar molecule, and a phosphate group.
There are two types of nucleic acids: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
The chemical composition of DNA nucleotides includes:
- Nitrogenous bases: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G)
- Deoxyribose sugar
- Phosphate group
The chemical composition of RNA nucleotides includes:
- Nitrogenous bases: Adenine (A), Uracil (U), Cytosine (C), and Guanine (G)
- Ribose sugar
- Phosphate group
The nitrogenous bases in nucleotides can be classified into two types: purines and pyrimidines. Purines are larger, double-ringed structures, while pyrimidines are smaller, single-ringed structures. Adenine and guanine are purines, while cytosine, thymine, and uracil are pyrimidines.
The sugar in DNA nucleotides is deoxyribose, while the sugar in RNA nucleotides is ribose. The difference between these sugars is the presence of a hydroxyl (-OH) group on the 2′ carbon of the ribose sugar, which is absent in the deoxyribose sugar.
The phosphate group in nucleotides is composed of a phosphorus atom bonded to four oxygen atoms. The phosphate group provides a negative charge to the nucleotide, which makes the DNA and RNA molecules negatively charged overall.
The arrangement of nucleotides in a DNA or RNA molecule forms a specific sequence, which carries genetic information. The sequence of nucleotides in a DNA molecule determines the sequence of amino acids in a protein, while the sequence of nucleotides in an RNA molecule serves as a template for protein synthesis.
What is Required Biomolecules Nucleic acids: Chemical composition
The required biomolecules for the synthesis of nucleic acids are:
- Nitrogenous bases: Adenine, Thymine, Cytosine, Guanine (in DNA) and Adenine, Uracil, Cytosine, Guanine (in RNA)
- Pentose sugar: Deoxyribose (in DNA) and Ribose (in RNA)
- Phosphate group
Nitrogenous bases are derived from amino acids, whereas pentose sugars are derived from carbohydrates. The phosphate groups come from high-energy molecules such as ATP.
The synthesis of nucleic acids requires a large amount of energy and specific enzymes. The process of nucleic acid synthesis is called DNA replication in the case of DNA and transcription and translation in the case of RNA.
During DNA replication, the double-stranded DNA molecule is separated, and each strand acts as a template for the synthesis of a new complementary strand. The nucleotides are added to the new strand in a specific sequence by DNA polymerase enzymes, with the help of other enzymes and proteins.
During transcription, the DNA sequence is used as a template to synthesize a complementary RNA molecule. The RNA nucleotides are added to the growing RNA strand in a specific sequence by RNA polymerase enzyme, with the help of other enzymes and proteins.
During translation, the RNA sequence is used to synthesize a protein molecule. The sequence of codons (three-nucleotide sequence) in the RNA molecule is read by ribosomes, which link amino acids in the order specified by the codons to form a protein chain.
When is Required Biomolecules Nucleic acids: Chemical composition
Nucleic acids, with their specific chemical composition of nucleotides, are required biomolecules in several important biological processes, including:
- Storage and expression of genetic information: DNA contains the genetic information that determines the traits and characteristics of an organism, and RNA is involved in the expression of this information through the synthesis of proteins.
- Transmission of genetic information: DNA is passed from one generation to the next through the process of DNA replication during cell division.
- Regulation of gene expression: RNA molecules, such as microRNAs, can regulate the expression of genes by controlling the stability and translation of messenger RNA molecules.
- Energy transfer: ATP, a molecule derived from nucleotides, is the primary source of energy for cellular processes.
- Enzyme catalysis: RNA molecules, called ribozymes, can act as enzymes and catalyze chemical reactions.
In summary, nucleic acids play a critical role in the transmission, storage, and expression of genetic information and are involved in several important biological processes, including gene expression regulation, energy transfer, and enzyme catalysis.
Where is Required Biomolecules Nucleic acids: Chemical composition
Nucleic acids, with their specific chemical composition of nucleotides, are found in all living organisms. They are present in the nucleus of eukaryotic cells, which contain DNA, and in the cytoplasm of both eukaryotic and prokaryotic cells, which contain RNA.
In eukaryotic cells, DNA is found in the nucleus, which is separated from the cytoplasm by a nuclear membrane. RNA, on the other hand, is found in both the nucleus and the cytoplasm.
In prokaryotic cells, which lack a nucleus, DNA is found in the cytoplasm, in the form of a circular chromosome. RNA is also found in the cytoplasm of prokaryotic cells.
Nucleic acids are also found in viruses, which can contain either DNA or RNA, but not both.
Overall, nucleic acids are present in all living cells and viruses, and are essential biomolecules for the transmission, storage, and expression of genetic information.
How is Required Biomolecules Nucleic acids: Chemical composition
Nucleic acids are made up of nucleotides, which are composed of three main components: a nitrogenous base, a pentose sugar, and a phosphate group.
The nitrogenous base can be either a purine or a pyrimidine. Purines have a double-ring structure and include adenine (A) and guanine (G), while pyrimidines have a single-ring structure and include cytosine (C), thymine (T) (in DNA), uracil (U) (in RNA).
The pentose sugar in DNA is called deoxyribose, while in RNA it is called ribose. Deoxyribose has one less oxygen atom than ribose.
The phosphate group is composed of a phosphate molecule bonded to the 5′ carbon of the sugar in the nucleotide.
The sequence of the nitrogenous bases along a nucleic acid strand determines the genetic code that is used to synthesize proteins or carry out other cellular functions.
The chemical bonds between adjacent nucleotides in a strand are called phosphodiester bonds, which are formed between the phosphate group of one nucleotide and the 3′ carbon of the sugar of the next nucleotide.
In summary, the chemical composition of nucleic acids is based on the three main components of nucleotides: a nitrogenous base, a pentose sugar, and a phosphate group. The sequence of these components along the nucleic acid strand determines the genetic code and the function of the nucleic acid molecule.
Structures of Biomolecules Nucleic acids: Chemical composition
The structures of biomolecules nucleic acids, including DNA and RNA, are based on the chemical composition of nucleotides.
DNA (deoxyribonucleic acid) is a double-stranded helix, composed of two strands of nucleotides running in opposite directions and held together by hydrogen bonds between complementary nitrogenous bases. The two strands of DNA are antiparallel, meaning they run in opposite directions. Adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G), forming complementary base pairs.
RNA (ribonucleic acid) is typically a single-stranded molecule, although it can form complex structures through intra-strand base pairing. RNA also contains four nitrogenous bases, but uracil (U) replaces thymine (T) and pairs with adenine (A), while cytosine (C) pairs with guanine (G).
The overall structure of nucleic acids is based on the specific sequence of nucleotides, which determines the information encoded in the molecule. The primary structure of a nucleic acid molecule is the linear sequence of nucleotides. The secondary structure of nucleic acids, such as the double helix of DNA, is formed by base pairing between complementary nucleotides. The tertiary and quaternary structures of nucleic acids are more complex and involve interactions between different parts of the molecule, including base stacking, hydrogen bonding, and interactions with other molecules.
In summary, the structures of biomolecules nucleic acids, including DNA and RNA, are based on the chemical composition of nucleotides and the specific sequence of these nucleotides determines the information encoded in the molecule. The structures of nucleic acids include primary, secondary, tertiary, and quaternary levels of organization.
Case Study on Biomolecules Nucleic acids: Chemical composition
One notable case study involving nucleic acids is the discovery of the structure of DNA by James Watson and Francis Crick in 1953.
Prior to their discovery, scientists had been working for decades to understand the nature of genetic material and how it was transmitted from generation to generation. In the early 20th century, the discovery of the chemical composition of DNA by Frederick Griffith and Oswald Avery showed that DNA was the genetic material in bacteria, but the structure of DNA was still unknown.
Watson and Crick, along with the help of Rosalind Franklin’s X-ray crystallography work, were able to deduce the double helical structure of DNA. Their model proposed that the two strands of DNA were held together by hydrogen bonds between complementary nitrogenous bases, with adenine pairing with thymine and cytosine pairing with guanine. The discovery of the structure of DNA was a major breakthrough in biology, as it provided a framework for understanding how genetic information is stored and passed on from one generation to the next.
Since the discovery of the structure of DNA, much research has been done to understand the roles of other nucleic acids, including RNA. RNA is involved in the transcription of genetic information from DNA and the translation of that information into proteins. The discovery of RNA’s functions has led to new fields of study, such as RNA interference (RNAi), which involves using RNA to target and silence specific genes.
Overall, the discovery of the structure of nucleic acids, specifically DNA, was a pivotal moment in the history of biology and has led to many important discoveries and advances in the field.
White paper on Biomolecules Nucleic acids: Chemical composition
Introduction:
Nucleic acids are the biomolecules that carry genetic information and are essential for the maintenance, replication, and expression of genetic information in living organisms. The chemical composition of nucleic acids is based on the structure of nucleotides, which are composed of three main components: a nitrogenous base, a pentose sugar, and a phosphate group. This white paper provides an overview of the chemical composition, structure, and functions of nucleic acids.
Chemical Composition:
Nucleotides are the building blocks of nucleic acids, and their chemical composition is crucial for the structure and function of these molecules. A nucleotide consists of a nitrogenous base, a pentose sugar, and a phosphate group. The nitrogenous base can be either a purine or a pyrimidine, and the most common purines are adenine (A) and guanine (G), while the most common pyrimidines are cytosine (C), thymine (T) (in DNA), and uracil (U) (in RNA). The pentose sugar in DNA is called deoxyribose, while in RNA it is called ribose. The phosphate group is composed of a phosphate molecule bonded to the 5′ carbon of the sugar in the nucleotide.
Structure:
The chemical composition of nucleotides forms the basis for the structure of nucleic acids. In DNA, the nucleotides are arranged in a double-stranded helix, with the two strands running in opposite directions and held together by hydrogen bonds between complementary nitrogenous bases. The base pairing between adenine and thymine, and between guanine and cytosine, is essential for the stability and replication of the DNA molecule. In RNA, the structure is typically single-stranded, although it can form complex structures through intra-strand base pairing. RNA also contains four nitrogenous bases, but uracil replaces thymine and pairs with adenine, while cytosine pairs with guanine.
Functions:
The primary function of nucleic acids is to carry and transmit genetic information. In DNA, the sequence of nitrogenous bases along a strand determines the genetic code that is used to synthesize proteins or carry out other cellular functions. RNA plays a crucial role in gene expression by carrying the genetic code from DNA to the ribosome, where proteins are synthesized. RNA also has other functions, such as catalyzing biochemical reactions and regulating gene expression through mechanisms such as RNA interference.
Conclusion:
Nucleic acids are essential biomolecules that carry genetic information and are involved in many cellular processes. The chemical composition and structure of nucleotides form the basis for the structure and function of nucleic acids. The discovery of the structure of DNA was a major breakthrough in biology, and since then, much research has been done to understand the roles of other nucleic acids, such as RNA. Understanding the chemical composition and structure of nucleic acids is crucial for understanding how genetic information is stored, transmitted, and expressed in living organisms.