Principles Of Inheritance And Variation Flashcards
Well known Indian breed of cow in Punjab -
Sahiwal
Gregor Mendel conducted hybridisation experiments on GARDEN PEA for _____years . From _to ____ .
7 yrs
1856-1863
During Mendel’s investigations into _____ it was for the first time that statistical analysis and mathematical logic were applied to biology .
Inheritance patterns
Mendels laws of inheritance
Mendels experiments had a _____ ,which gave greater credibility to the data he collected .
Large sampling size
Mendel conducted_______ experiments on ____breeding pea lines .
Artificial pollination /cross pollination experiments
True breeding
A true breeding line is one that , having undergone _________ , shows stable _____and _____for several generations .
Continuous self pollination
Stable trait inheritance
Expression
Mendel selected _____true breeding pea plant varieties as pairs , which were similar except for 1 character with contrasting traits .
14
Name the contrasting traits studied by Mendel in pea -
Stem height Flower colour Flower position Seed colour Seed shape Pod colour Pod shape
In F1 generation , ___trait as observed and in F2 , both the traits were expressed in the ratio_____ ( phenotypic ratio in monohybrid cross )
One of the parental trait only
3:1
Segregation meaning -
Separation ; isolation
Recessive parental trait is expressed without any _____ in the ____generation .
Blending
F2
When plants produce gametes by meiosis , the alleles of the parental pair ___ from each other and only 1 allele is transmitted to a gamete .
Segregate /separate
Segregation of alleles is a _____process .and there is ___chance of a gamete containing either allele .
Random
50%
Punnett square was developed by a ____ , named Reginald C Punnett .
British geneticist
When Mendel self -pollinated the F2 plants , he found that -
Dwarf F2 continued to generate dwarf plants in F3 and F4 .
Test cross is used to determine __composition .
Genotypic
______can be calculated using mathematical probability , by simply looking at the phenotype of a dominant trait , it is not possible to know ______ .
Genotypic ratios
Genotypic composition
Whether a tall plant from F1 or F2 has TT or Tt composition can be predicted using -
Test cross
In a typical test cross ,an organism showing a _____ and whose ____is to be determined , is crossed with the _____ instead of self-crossing
Dominant phenotype
Genotype
Recessive parent
Based on his observations on monohybrid cross , Mendel proposed 2 rules to consolidate his understanding of inheritance. These rules are called _____ . Name them .
Principles or Laws of Inheritance
1st law -law of inheritance
2nd law - law of segregation
Give the 3 postulates of LAW OF DOMINANCE -
1) chars are controlled by discreet units called FACTORS .
2) factors occur in pairs
3) in a dissimilar pair of factors one member if a pair dominates the other .
____law states that the ALLELES do not show any blending and that both the chars are recovered as such in F2 gen , though one of these is not seen at the F1 stage .
Law of segregation
Though the parents contain 2 alleles during gamete formation , the factors or alleles of a pair _____ from each other such that a gamete receives only one of the 2 factors .
Segregate
Sometimes the F1 had phenotype that did not resemble either of the 2 parents and was in btw the 2 . This phenomenon is called -
Incomplete dominance