Genetics

Genetics is a branch of natural science that deals with heredity due to the transmission of genes, gene regulation, and gene manipulation.

Genetics is a connecting link between many disciplines like microbiology, biotechnology, medicine, and agriculture.
Studies involving genes and chromosomes of living beings began quite late as it requires significant advances in the microscopy area.
The influence of heredity and its application of cultivation and production improved organisms, however, had been recognized since ancient times.
The study of genes and genetics began as a major concept after studies made by Mendel on pea plants. It was further strengthened and flourished by the works of Morgan.
Eventually, genetics became a distinct area of study with the identification of genes and the study of genes at different levels, including their role in the cell, their regulation, and their expression.
Initially, genetics was limited to understanding the concept and process of heredity via techniques like the formation of Punnet’s square. With the development of techniques like X-ray diffraction, the structure of DNA, and the presence of genetic code were established. This paved the way for modern genetics.
Modern genetics focuses on the chemical composition of structures found in genes like the DNA that influences the chemical reactions taking place in the cell.
Gene expression is influenced by two major factors; the genetic composition and the influence of the environment.
The influence of the environment on gene expression can be distinctly observed in green plants where the gene responsible for the formation of chlorophyll is only expressed in the presence of sunlight.
Genes, through the proteins they encode, determine how efficiently foods and chemicals are metabolized, how effectively toxins are detoxified, and even how vigorously infections are targeted.
Processes like mutations are now a significant cause of major genetic diseases. The mutations might arise due to a complex combination of genetic, behavioral, and environmental factors.

Types of Mutations

February 4, 2021October 16, 2018 by Sagar Aryal

The mutation is a process that produces a gene or chromosome that differs from the wild type (arbitrary standard for what “normal” is for an organism). The mutation may result due to changes either on the gene or the chromosome itself. Thus, broadly mutation maybe: Gene mutation where the allele of a gene changes. Chromosome mutation where segments of chromosomes, …

Prokaryotic and Eukaryotic Chromosomes

February 4, 2021September 24, 2018 by Sagar Aryal

The genome of an organism encompasses all of the genes of that organism. Gene is a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule. Thus a protein-coding gene is defined as a region of DNA that encodes a single polypeptide or a set …

Mendel’s Experiment and Laws

February 4, 2021September 21, 2018 by Sagar Aryal

In the 1860’s, an Austrian monk named Gregor Mendel introduced a new theory of inheritance based on his experimental work with pea plants. Mendel believed that heredity is the result of discrete units of inheritance, and every single unit (or gene) was independent in its actions in an individual’s genome. According to this Mendelian concept, inheritance of a trait depended on …

Chromosome- Structure, Types and Functions

February 4, 2021September 19, 2018 by Sagar Aryal

In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure. Chromosomes were first described by Strasburger (1815), and the term ‘chromosome’ was first used by Waldeyer in 1888. They appear as rod shaped dark stained …

Mutation- Causes, Mechanisms, Agents and Significance

February 4, 2021September 17, 2018 by Sagar Aryal

Mutation is a process that produces a gene or chromosome that differs from the wild type (arbitrary standard for what “normal” is for an organism). It is most commonly defined as a spontaneous permanent change in a gene or chromosome which usually produces a detectable effect in the organism concerned and is transmitted to the offsprings. Mutated gene or chromosome …

Characteristic of Genetic Code

February 4, 2021August 30, 2018 by Sagar Aryal

The genetic code is the set of rules by which a linear sequence of nucleotides specifies the linear sequence of a polypeptide. That is, they specify how the nucleotide sequence of an mRNA is translated into the amino acid sequence of a polypeptide. Thus, the relationship between the nucleotide sequence of the mRNA and the amino acid sequence of the …