Question

What is heritability and how does it play out in both long and shoet term selection of characteristics?

Answer 1

Heritability is a term or statics which is used in proportion to phenotype variation that can be passed to offspring. The proportion of difference between individual that is due to additive gene effects. It is field of genetics and breeding that estimate or provide the degree of variation in the phenotypic trait in a population.these observed variation in a particular trait can be attributed to inherited genetic factor in contrast to environmental ones.There are some early concept of heredity is- gene plasma theory state that all cells contain a complex set of genetic information.

Mendelian inheritance -- traits are inherited in accord with defined principles.

Heritability play a role in both short as well as long term selction of characterist.

In short term the characters are not passed to generation to generation. Eg use and disuse of organs.

--> characteristics that exhibit a continuous distribution of phenotype are termed Continuous characteristic.

It is arise because of gene at many loci inherited to produce the phenotype.eg. a single locus with two allele encodes a characteristic. Then their are 3 genotype possible AA, Aa, aa.

Characteristics is determined by 8 loci , with two allele then there are 6561 different genotype. Each genotype produce different phenotype.

Characteristics encoded by genes at many loci are called polygenic characteristics.

Many continuous characteristics are both polygenic and influencing by environmental factor, such characteristics are called multifactorial characteristics. Such continuous character are long term .Allele at each locus follow Mendelian principle and are inherited in same way as allele encoded simple , discontinuous characteristics. This exihibit few distinct phenotype. Hence heritability plays important role in selection of characteristics.