Non-Mendelian Genetics quiz Flashcards

Pleiotropy is when a single gene affects multiple different phenotypic traits.

Marfan syndrome is an example of pleiotropy, where a mutation in the FBN1 gene affects traits such as body height, limb length, spine curvature, and heart conditions.

Polygenic inheritance involves multiple genes affecting one trait, while pleiotropy involves one gene affecting multiple traits.

In acidic soil, hydrangea flowers tend to be blue, while in basic soil, they tend to be pink.

Multifactorial characters are phenotypes influenced by both genetic factors, such as alleles, and environmental factors, such as temperature or pH.

A pedigree is a chart or family tree used to track a phenotype over many generations.

Circles represent females and squares represent males.

Shaded shapes indicate individuals that have the phenotype of interest.

Horizontal lines represent mating parents.

Vertical lines connect parents to their offspring.

A mutation in the FBN1 gene limits the body's ability to build connective tissue, leading to multiple phenotypic effects.

Environmental factors such as temperature and pH can influence the expression of multifactorial characters alongside genetic factors.

Alleles are genetic factors that contribute to the inheritance of multifactorial characters.

It indicates that the connected individuals are siblings from the same set of parents.

A single gene mutation in pleiotropy can lead to multiple, seemingly unrelated phenotypic effects.

A gene that shows maternal effect inheritance is one where the phenotype of the offspring is determined by the genotype of the mother, rather than the genotype of the offspring itself. This is because the mother's genotype influences the environment of the developing embryo, often through substances deposited in the egg.

An exception to the one gene–one enzyme hypothesis is pleiotropy, where a single gene can affect multiple phenotypic traits, rather than just one enzyme or function. This is exemplified by conditions like Marfan syndrome, where a mutation in a single gene affects various body systems.