GENETICS

Punnett square: Introduction, construction, Applications

Introduction: The Punnett square is a table that show all the expected percentage of different genotypes in the offspring outcomes for a genetic cross between two individuals with known genotype. It is named after British geneticist, Reginald C. Punnett (1875–1967). It consists of a square which is divided into four quadrants to predict the chances […]

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Extrachromosomal Inheritance: Introduction, Types, Examples

Introduction: Extrachromosomal Inheritance in eukaryotes: Various scientists have investigated extrachromosomal inheritance in different eukaryotes. Some of the most significant examples of extranuclear inheritance in eukaryotes are as follows: Plastid inheritance Correns and Baur found that the four o’ clock plant, Mirabilis Jalapa, in contrast to other higher plants, contain three types of leaves and parts

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Genetic drift:  Introduction, Types, Roles

Introduction: Types: The Bottleneck Effect  (Reduction in the population size) Natural occurrences such as deteriorating environmental conditions like natural disaster, flood, earthquake, fires, volcanic eruptions can potentially increase genetic drift. The bottleneck effect occurs when just a few individuals survive, reducing variance in the population’s gene pool. The genetic structure of survivors becomes the genetic

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Pseudogenes: Introduction, Types, Features

Introduction: Genes, also labelled as “junk” DNA, are inheritable genetic elements whose sequence are naturally similar to functional genes. However, they do not code for protein because they lack coding potential due to the presence of disruptive mutations such as frame shifts, premature stop codons, internal deletion or insertion relative to the normal sequence, Hence,

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Satellite DNA (satDNA):  Introduction, Types, Features, Applications

Introduction: Satellite DNA (satDNA) also known as tandemly repeated DNA (TR-DNA), is the highly repetitive DNA consisting clusters of short repeated sequences i.e., same sequence of nucleotides is repeated many times in tandem within the genome. Generally, it possesses a variable AT-rich repeat which are predominately located at heterochromatic regions, which are found mostly in

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Extrachromosomal Inheritance: Introduction, Plastid inheritance, Mitochondrial Inheritance, Maternal effect

Introduction: The genes of nuclear chromosome have different roles in inheritance, cellular metabolism, development and mutation of the organism in which they occur. The gens of nuclear chromosomes have a significant and key role in the inheritance of almost all characters from one generation to other generation. However, they alone cannot be considered as the

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Crossing over: Introduction, Types, chromosomal Map, Interference, Coincidence and Significance

Introduction: Crossing over is the refers to the interchange of genetic material between non-sister chromatids of homologous chromosomes involving breakage and reunion at precise point during meiotic prophase (pachytene), which results in new allelic combinations in the daughter cells. In 1912, the term crossing over was first used by Morgan and Cattell. Diploid cells have

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Cystic Fibrosis

Cystic Fibrosis- Definition, Symptoms, Diagnosis, Treatment

Introduction: Cystic fibrosis (CF) is a hereditary condition that impacts the respiratory, digestive, and reproductive systems. It is caused by a mutation in the gene that codes for a protein called cystic fibrosis transmembrane conductance regulator (CFTR). This protein regulates the movement of salt and water in and out of cells, and is involved in

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