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 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
| No Of gene pair | Phenotype | Genotype |
| 1 | 2 | 3 |
| 2 | 4 | 9 |
| 3 | 8 | 27 |
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
answer