Competitive Exams: Revision Terminology Part 9

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Light Dark forms (Both belong to one sp. Now as 2 forms – typical & carbonaria of B. betularia)

Hybrid breakdown – when offspring of hybrids are infertile

Cell anemia – glutamic acid is replaced by valine in the 6 Beta position of autosomal recessive lethal gene = 0.4 frequency of carrier in population of 200 individual is die due to lethal So and , So freq. of carrier

Hot spots – sites which are more mutable then other sites (Benzer) e. g. smethyl Cytosine residues

More closely related sexual partners less are variations in their off springs.

Classical/forward genetics – study of phenotype, analysis & isolation of concerned genes & study of DNA sequence comprising genes.

Reverse genetics – if we start DNA Seq. study from phenotypic effect of which we do not know & then introduce in some animal to study its phenotypic effect.

Blending of inheritable chromosome is the intermingling of heredity material of both offspring՚s.

Mendel՚s success – pea easy to cultivate, naturally self-pollinated, artificially cross-pollinate.

Mendel՚s success – sharply defined inherited differences in difference varieties, only one variable at a time

In rr seeds in small DNA Fragment interferes with SBE – 1 so starch in not formed and it accumulates as sugar – causer high osmotic pressure lead to shrinkage & wrinkling.

Dihydric cross - inheritance of seed color is independent of seed shape.

Homozygous - condition in which only one allele is present of a pair

Mendel used element for factor ⇾ gene

Genotype Exhibiting Difference Phenotype

Genotype exhibiting difference phenotype under difference environmental conditions – Individual norm of reaction

Same environment & genotype but phenotype differ due to difference in internal environment = Developmental noise

2 different genotype produce same phenotype due to different environment & have difference genotype = phenocopies of each other

If a dwarf plant introduced tall by gibberellin acid then too it would behave as dwarf genetically.

In haploid organism – chromosome are governed only by one allele then law of dominance & Segregation do not apply.

Locus = position of allele on chromosome

Back cross Tt X any parent

Test cross Tt X recessive (tt) Phenotype = 1: 1: 1: 1

Hugo – de Vries (Dutch) cosrrens (Germany) Tschermark (Austrian) ⇾ Mendel՚s work as principles & coined term factor

Bateson – 1st announced Mendel՚s work in England (poultry, rabbit, sweet pea)

Bateson coined homozygous, heterozygous, allomorphs – “Mendel՚s principle of heredity”

Nageli advised Mendel to work on Hieracium (But he failed) seeds produced without pollination

Mendel = 1st genetic surgeon

Genotype and Phenotype
No Of gene pairPhenotypeGenotype

Genetic markers ➾ Alleles.

Albinism = autosomal recessive mutation. If 1st child of a normal pair in albino what is the is the probability of 2nd child for albino = 25 % (due to recessive chromosome so only homozygous condition will show albinism)

Tt x Tt ⇾ tt (25 %) = answer

1st child is independent of the 2nd child

What would be proportion of Tt Yy Ss Dd Ee from a cross

Tt Yy Ss Dd Ee X Tt Yy Ss Cc Dd Ee

Answer: of progeny will be