Difference Between Gene and DNA: DNA and Genes?

DNA is the genetic material found in all living organisms. A gene is a specific segment of DNA that carries the code for making proteins. Genes determine traits and functions in an organism. So, all genes are made up of DNA, but not all DNA is a gene. The difference between a gene and DNA is that DNA is the full code, while a gene is just a part of that code. The difference between a gene and DNA is a basic part of the molecular basis of inheritance, which explains how traits are passed through DNA and genes.

This Story also Contains

1. What is DNA?
2. Function of DNA
3. What is a Gene?
4. Function of Genes
5. Differences Between Gene And DNA
6. MCQs on Genes and DNA

The difference between genes and DNA is important in genetics and biology. Genes act like instructions to make proteins, while DNA is the complete instruction book in biology. The genetic code is stored in the DNA, and each gene uses a specific part of this code to produce proteins. While DNA serves as the entire genetic outline, genes are the functional units within it. In this article, genetics, DNA, and the difference between genes and DNA are discussed.

What is DNA?

DNA stands for Deoxyribonucleic Acid, a large and complex molecule that contains the genetic instructions applied in the growth, development, functioning, and reproduction of known living organisms and many viruses.

DNA Structure

DNA has a unique double-helix structure that is twisted into a ladder. Such a structure consists of the following elements:

• Nucleotides: They are commonly referred to as the fundamental structural and functional units of DNA. Each nucleotide is comprised of a sugar molecule, a phosphate group, and a nitrogenous base.

• Sugar-Phosphate Backbones: They form the backbone of the ladder and are made of alternating sugar, deoxyribose, and phosphate groups.

• Nitrogenous Bases: The rungs of the ladder; pairing is specific between Adenine (A) and Thymine (T) and between Cytosine (C) and Guanine (G).

Function of DNA

DNA plays a vital role in all living organisms as it stores genetic information needed for growth, development, and functioning. It acts as a blueprint that carries instructions for building proteins and controlling various life processes. DNA forms the backbone of critical activities in living organisms, including:

• Storage of Genetic Information: DNA contains instructions regarding the construction and functioning of an organism.

• Role in Heredity and Variation: DNA provides for the transfer of genetic information from parents to offspring, hence contributing to genetic diversity.

• Role in Mutation and Evolution: DNA undergoes mutations that lead to genetic variation and drive the process of evolution.

Types of DNA

• Nuclear DNA: It is found in the nucleus of the cell and codes for most of the genetic information.

• Mitochondrial DNA: It is found in the mitochondria and has some metabolic functions.

What is a Gene?

A gene is a succession of nucleotides in the DNA molecule containing enough information to form a functional product, usually a protein. Genes are units of heredity and include information necessary for guiding the development, function, and reproduction of organisms.

Gene Structure

The structure of a gene is complex, with the following regions:

• Exons: Those regions that code for a specific sequence of amino acids.

• Introns: These are noncoding regions that are spliced out in the processing of RNA.

• Promoters and Enhancers: Regulatory sequences that control the expression and time of gene activation.

Function of Genes

Genes play a central role in the functioning of all living organisms. One of their primary functions is coding for proteins. Genes contain specific sequences of DNA that serve as instructions to build proteins. Genes have various crucial functions, including:

• Coding for Proteins: They carry the blueprint to synthesize proteins, which facilitate several cellular activities.

• Regulation of Biological Processes: Genes act as regulators for different biological processes by controlling when and how proteins are produced.

Types of Genes

• Structural Genes: Encode proteins for some part of the structure of the body.

• Regulatory Genes: Control the expression of other genes.

• Housekeeping Genes: Maintain the fundamental cellular functions necessary for the survival of the cell.

Differences Between Gene And DNA

Genes are small parts or segments of this DNA, and they carry the information for specific traits like eye color, height, or making a protein. So, genes are like small instructions written inside the big instruction book called DNA. It is one of the important Differences and comparisons articles in Biology. The points for gene and DNA differences are given below:

MCQs on Genes and DNA

Question: Which of the following statements about DNA is correct?

1. DNA is a double-stranded molecule made up of amino acids.

2. DNA carries the genetic information in the form of genes.

3. DNA is found only in the nucleus of cells.

4. DNA is a protein that provides structural support to cells.

Answer: DNA (deoxyribonucleic acid) is a double-stranded molecule made up of nucleotides, not amino acids. It carries genetic information in the form of genes, which are specific sequences of DNA that provide instructions for the synthesis of proteins and other molecules. DNA is found in the nucleus of cells, but it can also be found in other cell organelles like mitochondria and chloroplasts. DNA is not a protein but a nucleic acid.

Hence, the correct answer is option 2) DNA carries the genetic information in the form of genes.

Question: Assertion: Genes determine the characteristics of an individual.

Reason: Genes code for proteins that are responsible for the physical and biological traits of an individual.

1. Both assertion and reason are true, and the reason is the correct explanation of the assertion.

2. Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

3. The assertion is true, but the reason is false.

4. The assertion is false, but the reason is true.

Answer: This assertion-and-reason-type question emphasizes the purpose and process of genetic testing. Genetic testing is a technique used to analyze an individual's DNA to identify specific genetic variations or mutations. It involves examining the DNA sequence for specific genes or regions of interest to determine if any alterations or abnormalities are present.

Genetic testing can be performed in various ways, including techniques such as polymerase chain reaction (PCR), DNA sequencing, or microarray analysis. These methods allow scientists to detect and analyze specific genetic variations or mutations, providing valuable information for diagnosis, risk assessment, and personalized treatment options.

Hence, the correct answer is Option (1) Both assertion and reason are true, and the reason is the correct explanation of the assertion.

Question: Which nitrogenous base is NOT found in DNA?

1. Adenine

2. Guanine

3. Uracil

4. Thymine

Answer: In DNA, the nucleotides are joined by phosphodiester bonds to form polynucleotide strands. The two strands in DNA are complementary and antiparallel. The structure of DNA is stabilized by hydrogen bonds between the complementary base pairs in DNA. DNA has nitrogen bases, namely purines (adenine and guanine) and pyrimidines (thymine and cytosine). Uracil is absent. The complementary base pairing in DNA is adenine (A) with thymine (T) and guanine (G) with cytosine (C).

Hence, the correct answer is option 3)Uracil

Also Read:

• MCQ on Gene and DNA

• Gene Regulation and Gene Expression

• Genetic Code And Mutation