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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.

Mendel’s 3 Laws (Segregation, Independent Assortment, Dominance)

May 19, 2022May 16, 2022 by Sagar Aryal
Mendel's Laws

In the 1860s, 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 … Read more

Dihybrid Cross- Definition, Steps and Process with Examples

May 19, 2022May 15, 2022 by Anupama Sapkota
Dihybrid Cross

Dihybrid Cross Definition A dihybrid cross is a type of genetic cross between two individuals with either homozygous or heterozygous genotypes of two characters or traits. The dihybrid cross is … Read more

Multiple Alleles- Definition, Principle, Examples, vs. Polygenic Traits

May 10, 2022May 8, 2022 by Khushi Jain
Multiple Alleles

Multiple alleles are the presence of two or more alternative forms of the same gene present in the population because of mutation in the haploid and diploid organism, which usually … Read more

Karyotype And Karyotyping- Definition, Procedure, Applications

May 6, 2022May 5, 2022 by Khushi Jain
Karyotype And Karyotyping

What is a Karyotype? The number and appearance of chromosomes (made up of DNA and supercoiled proteins) in an organism is known as a karyotype. There are 2 kinds of … Read more

Mendel’s Law of Dominance- Definition, Examples, Limitations

May 19, 2022April 17, 2022 by Anupama Sapkota
Mendel’s Law of Dominance

Mendel’s Law of Dominance Definition Mendel’s Law of Dominance states that ‘In crossing between homozygous organisms for contrasting characters of a pair, only one character of the pair appears in … Read more

Mendel’s Law of Segregation- Definition, Examples, Limitations

May 19, 2022April 17, 2022 by Anupama Sapkota
Mendel's Law of Segregation

Mendel’s Law of Segregation Definition Mendel’s Law of Segregation states that ‘The hybrids or heterozygotes of F1 generation have two contrasting characters of dominant and recessive nature where the alleles … Read more

Punnett Square- Definition, Types, Application, Examples, Limitations

May 19, 2022March 30, 2022 by Anupama Sapkota
Punnett Square in Pea Plant

Punnett Square Definition The Punnett square is a table or checkboard grid that is used to determine all possible genotypes from a particular cross. Punnett square is a simple square … Read more

Somatic Mutation vs. Germline Mutation- 13 Major Differences

May 3, 2022March 24, 2022 by Prashant Dahal
Somatic Mutation vs. Germline Mutation

A mutation is defined as the sudden change in gene i.e. nucleotide sequences in DNA, which may be qualitative or quantitative change. This may or may not be inheritable. Mutations … Read more

Test Cross (Single, Two, Triple Gene)- Definition, Examples, Uses

May 2, 2022March 23, 2022 by Prashant Dahal
Test Cross Types and Examples

Phenotypic characters can be easily separated just by looking at the individual. It’s not that easy to determine the genotypic character of that same individual. This is because, genetically a … Read more

Divergent Evolution- Definition, Causes, Examples

May 1, 2022March 19, 2022 by Bikash Dwivedi
Divergent Evolution

Evolution refers to the series of gradual changes that can be observed in an organism from ancestors to predecessors in a longer period which can be genetic or phenotypic. Evolution … Read more

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