#polymorphism

Basic Evolution

Which does NOT maintain polymorphism?

Positive frequency dependence reflects key principle in quiz on section a solved pyqs, where evolutionary mechanisms shape genetic variation and adaptation. In this context, Positive frequency dependence aligns with experimental and theoretical evidence from population genetics, behavioral ecology and molecular phylogeny. Textbooks like Campbell Biology, Futuyma Evolution and Hartl Principles illustrate supporting data. Understanding why Positive frequency dependence fits helps integrate natural selection,

Ref: Campbell Biology, Evolution Chapters, Selection Types.

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Basic Evolution

Balancing selection maintains:

Genetic variation reflects key principle in quiz on section a solved pyqs, where evolutionary mechanisms shape genetic variation and adaptation. In this context, Genetic variation aligns with experimental and theoretical evidence from population genetics, behavioral ecology and molecular phylogeny. Textbooks like Campbell Biology, Futuyma Evolution and Hartl Principles illustrate supporting data. Understanding why Genetic variation fits helps integrate natural selection, environment.

Ref: Campbell Biology, Evolution Chapters, Selection Types.

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Molecular Marker

The polymorphism detected by RFLP is due to:

Restriction fragment length polymorphism originates when nucleotide substitution, insertion or deletion abolishes or creates a specific recognition sequence for a restriction endonuclease. Digestion then yields fragments of altered length detected by gel electrophoresis or Southern blotting after hybridization with labeled probes. This change segregates in Mendelian fashion as allelic variation inherited codominantly. It does not involve repeat expansion, primer binding differences observed in RAPD, or slippage mispairing responsible for microsatellite instability. Thus, point mutations at restriction sites underlie observed band polymorphism pattern.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

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Molecular Marker

What is the minimum number of alleles needed for polymorphism?

Polymorphism in genetics is defined as the occurrence of two or more discontinuous allelic variants at a locus in a population, with the most common allele having a frequency less than ninety five to ninety nine percent depending on definition used. Therefore, a minimum of two alleles is strictly required to consider a locus polymorphic. A single allele indicates monomorphism providing no genetic information. Higher allele numbers increase polymorphism but the threshold for classification as polymorphic remains presence of an alternative variant enabling diversity studies.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

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Molecular Marker

Which of the following is monomorphic?

All listed sequence features represent highly variable regions of the genome. Short tandem repeats, insertion-deletion polymorphisms and simple sequence repeats show length or sequence variation among individuals due to replication slippage or transposable element activity. They are extensively used as polymorphic markers because mutation rates are high and multiple allelic forms exist in populations. Monomorphic loci, by definition, show a single invariant allele across all genotypes and lack informativeness for diversity analysis, which does not apply to these hypervariable marker classes.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

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