What is Termed as Molecular Biology?
If you don’t know “What is molecular biology” then you should know it is a division of biology that deals with the study of biological components and their interactions besides a collection of processes that are developed because the genesis of the field has authorized scientists to learn a lot about the processes of molecules. Living things are created from chemicals similar to non-living things. Hence, a molecular biologist studies the method in which a molecule does have an interaction with one another for performing various functions of life.
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The Job of the Molecular Biologists
Molecular biologists conduct various experiments for investigating the function, structure, regulation, processing, and evolution of various biological molecules besides their interactions with each other. Hence, they propose micro-level perception into the working of life.
What is the Molecular Biology of the Gene?
Though there are present various types of molecules in living things, the majority of molecular biologists concentrate on proteins and genes. Proteins are useful for performing a huge array of functions that happen within a living cell, whereas molecular biology of the gene comprises the info that is needed for making more proteins. This way, molecular biologists study the molecular biology of the gene.
Why is the History of Molecular Biology?
Though molecular biology is hugely important in the modern-day life sciences, it has got its roots in the 1930s and 1940s, and it had turned institutionalized during the 1950s and 1960s too. Hence, it does not seem surprising that numerous philosophical matters that are involved in molecular biology happen to be closely entangled with recent history. There are four aspects of the development of molecular biology, and they are:
Its origins
Its classical era
Its migration into different domains of biology
Its turn to genomics as well as post-genomics
What is the Central Dogma of Molecular Biology?
The central dogma describes the method by which DNA gets recorded into RNA. After this, it is translated into protein. To understand the functions, structures, and internal controls that happen in individual cells, you need to understand molecular biology well. These processes are important to target new drugs, diagnose disease, and understand cell physiology efficiently.
A few medical therapies, as well as clinical research that arise from molecular biology, get encompassed under gene therapy. However, the utilization of molecular cell biology or molecular biology in medicine is known as molecular medicine.
The central dogma explains that when the info has entered into protein, it fails to get out from it. To put it in detail, it is the transportation of info to nucleic acid from a nucleic acid or to protein from the nucleic acid. However, transfer to nucleic acid from protein or to protein from protein is impossible. The info means the exact determination of the series.
Molecular Biology Techniques
Molecular biology is the area of biology that is related to the method of gene transcription for yielding RNA and change of RNA into proteins. Some techniques that are utilized in molecular biology are:
PCR or Polymerase Chain Reaction - It is one of the highly vital techniques that are utilized in molecular biology. PCR permits only one DNA sequence to get amplified into countless DNA molecules. It is also useful for introducing mutations in the DNA or making familiar restriction enzyme areas. PCR is also useful for determining whether or not a specific fragment does exist in some cDNA libraries. Some kinds of PCR comprise RT-PCR (reverse transcription PCR) and quantitative PCR or QPCR.
Expression Cloning - Expression cloning is helpful to scientists in understanding the functions of the protein. The DNA which codes for a specific protein gets copied or cloned through the use of PCR into some expression vector known as a plasmid.
Macromolecule Blotting & Probing - Some processes, like northern blotting, Southern blotting, eastern blotting, and western blotting, are useful for transferring RNA or DNA proteins into a blotting membrane.
Gel Electrophoresis - Gel electrophoresis is another vital technique that is utilized in molecular biology. This is used for separating proteins, RNA, and DNA according to their sizes by applying some electric field because the DNA is run via agarose gel.
Arrays - A DNA chip is considered an accumulation of many DNA spots that are mounted on some solid surface, like a microscope slide. It is utilized for quantifying the levels of protein expression all across many numbers of genes. This process is also utilized for genotyping different genomic regions.
Thus, the article has covered all the important information related to molecular biology for you to understand the topic better.
FAQs on Molecular Biology
1. What is molecular biology?
Molecular biology is a specialised field of science that studies the composition, structure, and interactions of cellular molecules like DNA, RNA, and proteins. It focuses on the molecular basis of biological activity, including how these molecules carry and express genetic information, which ultimately governs all life processes within an organism.
2. What is the Central Dogma of molecular biology?
The Central Dogma describes the flow of genetic information within a biological system. Proposed by Francis Crick, it states that information flows from DNA to RNA to protein. This process involves two main steps:
- Transcription: The genetic information from a segment of DNA is copied into a messenger RNA (mRNA) molecule.
- Translation: The mRNA sequence is used as a template to synthesize a specific protein at the ribosome.
3. What are the main structural differences between DNA and RNA?
While both are nucleic acids, DNA and RNA have key structural differences:
- Sugar: DNA contains deoxyribose sugar, whereas RNA contains ribose sugar, which has an extra hydroxyl group.
- Bases: DNA uses the nitrogenous bases Adenine (A), Guanine (G), Cytosine (C), and Thymine (T). In RNA, Thymine is replaced by Uracil (U).
- Structure: DNA is typically a double-stranded helix, while RNA is usually a single-stranded molecule.
4. How does the long DNA molecule get packaged into a compact structure within a cell's nucleus?
The packaging of the very long DNA molecule into a tiny nucleus is a remarkable feat of biological engineering. In eukaryotes, this is achieved through a multi-level coiling process. The negatively charged DNA strand wraps around a core of positively charged proteins called histones to form a structure known as a nucleosome. These nucleosomes, often described as 'beads on a string', are further coiled and condensed to form chromatin fibres, which then supercoil to form the highly compact chromosome visible during cell division.
5. Why is the genetic code described as 'degenerate' and what is its significance?
The genetic code is called 'degenerate' or redundant because multiple codons (sequences of three nucleotides) can specify the same amino acid. For example, both UCU and UCC code for the amino acid Serine. The significance of this is that it provides a buffer against mutations. A point mutation in the third base of a codon may not change the resulting amino acid, thus having no effect on the final protein structure and function. This property contributes to the stability of the genetic information.
6. How does the lac operon serve as a model for gene regulation?
The lac operon in E. coli is a classic example of how genes can be turned on and off in response to the environment. It consists of a promoter, an operator, and three structural genes that code for enzymes to metabolise lactose.
- In the absence of lactose, a repressor protein binds to the operator, physically blocking RNA polymerase from transcribing the genes. The operon is 'off'.
- When lactose is present, it acts as an inducer, binding to the repressor and changing its shape. The repressor can no longer bind to the operator, allowing transcription to proceed. The operon is 'on'.
7. What are some key laboratory techniques used in molecular biology?
Molecular biologists use several powerful techniques to study and manipulate nucleic acids and proteins. Some fundamental examples include:
- Polymerase Chain Reaction (PCR): A method to amplify a specific segment of DNA, creating millions of copies from a small sample.
- Gel Electrophoresis: A technique used to separate DNA, RNA, or protein molecules based on their size by pushing them through a gel matrix with an electric field.
- Blotting (Southern, Northern, Western): Processes used to transfer and detect specific DNA, RNA, or protein sequences from a gel to a membrane for further analysis.
8. How do retroviruses, like HIV, challenge the traditional Central Dogma?
Retroviruses present a notable exception to the one-way flow of information in the Central Dogma. These viruses have RNA as their genetic material. Upon infecting a host cell, they use a special enzyme called reverse transcriptase to synthesize DNA from their RNA template. This process, known as reverse transcription (RNA to DNA), is the opposite of the standard transcription process. The newly synthesized viral DNA is then integrated into the host cell's genome, allowing it to be transcribed into new viral RNA and proteins.
