Principles of Genetics


Genetics is the process of bearing the characteristics of one to another generation. Additionally, via genetics, it's possible to spread normal elements that are noticeable in humans as well as animals, such as colours, shape, and even some diseases. Moreover, according to biology, genetics refers to the study of hereditary and the transmission of the features that are available in the body, such as contrast and similarities, from parents to children.

What is Heredity?

In tutorials on biology, heredity refers to passing the characteristics to the next generation. The procedure of heredity appears among all the different living organisms across the globe including plants, animals, bacteria, fungi, and human beings.

Figure 1: Building blocks of genetics

Heredity and genetics are connected to understanding the process of inheritance among the living being in this universe. DNA contains valuable information regarding heredity. So in the process of collecting information about the transmission of characteristics from parents to their children among humans or animals, DNA signifies a valuable part. Moreover, due the DNA formation, basic functions work properly in the living organisms, such as the development of proteins in the body.

DNA plays a crucial role in giving distinctive information about the colour of eyes, different health issues, and others.

History of Genetics

Genetics is represented as the science that deals with the mechanisms of liability for the distinctions and similarities. The phrase genetic was issued by W Bateson in 1905. Genesis is the origin of the word genetics which represents the meaning of growing into. Additionally, it signifies the study of transmitting different attributes in the body.

Figure 2: Basics of gene


Variation is the distinction among the individual or group organisms in the same species due to the distinction by genetics. The mentioned distinction among the species is due to the available environmental factors. The factor of metabolism, learning, behaviour, and capability refers to the characteristics. These traits are inherited among the next generations. Genetics can be defined as a process that helps the identification of inheritance.

Types of Variation

There are additional classes of variations that are included in the tutorials on genetics. The followings are the types of variations −

Genotypic Variations

It causes distinctions among the number of the chromosome structure. Humans contain 23 pairs of chromosomes and the distinctions in the genes that are carried by chromosomes are visible in the genotypic variations. The formation of the genetic numbers is noticeable in the living organisms by eye, colour, body forms, and height. With simple observations, genotypes cannot be visible. However, it can be observed in the breeding experiments that are performed under a controlled condition of the environment.

Somatic Variations

With the exception of the germ cells (sperm and egg), somatic variations can arise in every cell of the body and are not therefore inherited by offspring. However, somatic variations do not always result in the development of cancer or other diseases.


It is defined as the characteristics transmission from the parents to their offspring. Heredity also defines the inheritance of different differences and passing them to the next generations.

Mendel’s Laws of Heredity

This principle of heredity or inheritance composed by Gregor Mendel remarks that traits are independently transmitted to offspring of one another. Additionally, Mendel executed the experiments of the Garden pea at the back of his garden to demonstrate the principle of heredity. For the experiment, he took 14 true-breeding pea plants with seven distinguishable traits. It defined the two opposite traits available in the pea plants. The factors or the genes that coded for a couple of opposite characteristics were named alleles. Based on this experiment, Mendel developed the Principle of Heredity or Inheritance.

Mendelian Disorders

According to the heredity law developed by Gregor Mendel, the followings are the common disorders due the genetics −

  • Cystic fibrosis

  • Colour blindness

  • Thalassemia

  • Haemophilia

  • Phenylketonuria

Mutation procedure

The procedure of mutation is a result of alternation in the sequencing of the DNA and it leads to altering the entity’s phenotype and genotype. Due to mutation, the process of variations is found in the DNA. The process of mutation can lead to different diseases and abnormalities in living beings. Changes in the pairs of DNA can be referred to as mutation.


Study of heridity helps in understanding how humans and other living beings carry their past characteristics. The investigation of the DNA sequence and genetics present in the living being helps with the broad knowledge on the analysis of the variation of the trait.


Q1. What is genetics?

Ans. The science behind the comprehension of the characteristics with the differences and similarities among living beings is genetics. In order to understand the variations in inheritance, genetics is the basics in biological tutorials.

Q2. What is the chromosomal theory of inheritance?

Ans. Chromosomes are pair of homologous that has two alleles where the gene is transferred from the parent couple. The homologous pair separates during the gamete formation process when meiosis takes place.

Q3. What does genetic mutation refer to?

Ans. The process of sequencing of DNA results in mutation in living beings. Viable mutations are inherited from one to another generation. The mutation is not always harmful and sometimes, it is to adapt to the environment whereas some mutations can lead to different diseases in the living organisms.