Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
THE LAWS OF 
MENDEL 
SUBMITTED TO: SUBMITTED BY : 
HIMANSHU BHATT
GREGOR MENDEL (1822-1884) 
 Austrian monk 
 Born in 1822 near Brunn in Austria, in a 
poor family. 
 Joined the St. Aug...
 But his findings were discarded due to the prevailing theories of 
Evolution. 
 Later on, his theories were again disco...
WHY PEA PLANT…?? 
Flower structure of pea ensured self-pollination 
and also, well defined male 
and female parts. 
Single...
Emasculation and pollination of pea 
flowers is quite easy. 
September 13, 2014 THE LAWS OF MENDEL
reproduce sexually. 
In the varieties available, several 
characters had two contrasting 
forms, which were easily 
distin...
HYPOTHETICO-DEDUCTIVE METHOD APPLIED BY 
MENDEL (APPARENTLY UNKNOWINGLY) 
Theory 
September 13, 2014 THE LAWS OF MENDEL
SEVEN PAIRS OF SIMPLE DIFFERENCES 
September 13, 2014 THE LAWS OF MENDEL
TERMINOLOGY 
• Character - morphological, anatomical or behavioral feature of an organism. 
• Allele - different alternati...
F1 generation : the hybrid offspring of the parental generation. 
F2 generation: the self fertilized progenies of F1 gener...
September 13, 2014 THE LAWS OF MENDEL
LAW OF DOMINANCE (GIVEN BY ERIC VON TSCHERMAK) 
 Every gene has two alleles that can code for a trait. 
 One allele is d...
F1 Tall plant (Tt) F1 Tall plant (Tt) Tall plant (TT) Tall plant (Tt) Dwarf plant (tt) 
. . . . . . . 
However, this law w...
LAW OF SEGREGATION 
•During the formation of gametes, the paired alleles separate (segregate) randomly 
so that each gamet...
•The pair of alleles of each parent separate and only one allele passes 
from each parent on to an offspring 
•Which allel...
 Mendel experiment , he crossed tall and dwarf 
varieties of garden peas. 
 F1 produced were tall. 
 When F1 were self-...
 When F1 plants from Mendel’s experiments were 
crossed back to the dwarf variety, half the progeny 
were tall and half d...
When a similar experiment was done with each pair of characters, 
the results were the same: 
September 13, 2014 THE LAWS ...
LAW OF INDEPENDENT ASSORTMENT 
 This law states that member of different pairs of alleles 
assort independently during th...
 Mendel crossed plants that differ in two pairs of alleles. 
e.g., round green seeds and wrinkled yellow seeds. 
 F1 hyb...
When Mendel crossed the F1 
generation obtained with the 
recessive parent, four different 
phenotype were obtained. 
It v...
September 13, 2014 THE LAWS OF MENDEL
September 13, 2014 THE LAWS OF MENDEL
September 13, 2014 THE LAWS OF MENDEL
WHY WAS MENDEL SO SUCCESSFUL..?? 
Studied the inheritance of only one pair of contrasting 
characters at a time. 
Select...
 Accurate and incisive analysis of the 
reasons. 
 His knowledge of mathematics was a 
definite asset for the interpreta...
NEGLECTION OF MENDEL’S FINDING : 
 Using mathematical principles was something new and unacceptable to 
the biologists. 
...
 Studies of Mendel appeared to establish the constancy of 
characters of a species generation after generation, which was...
BIOLOGICAL SIGNIFICANCE OF MENDEL’S 
LAWS 
It showed the pattern of inheritance of the character from parent to the 
offs...
 It also provided the reason for variation in offspring 
transferred from the parents to the offspring in the 
form of ge...
“Genetics has moved far head than the protoidea that had been laid down by Mendel , but still the 
science owes its existe...
You’ve finished this document.
Download and read it offline.
Upcoming SlideShare
Mendels law
Next
Upcoming SlideShare
Mendels law
Next
Download to read offline and view in fullscreen.

Share

THE LAWS OF MENDEL

Download to read offline

MENDEL'S LAWS AND THEIR IMPORTANCE

Related Books

Free with a 30 day trial from Scribd

See all

THE LAWS OF MENDEL

  1. 1. THE LAWS OF MENDEL SUBMITTED TO: SUBMITTED BY : HIMANSHU BHATT
  2. 2. GREGOR MENDEL (1822-1884)  Austrian monk  Born in 1822 near Brunn in Austria, in a poor family.  Joined the St. Augustinian monastery .  Was sent to University of Vienna.  Presented his findings before National History Society of Brunn in 1965. September 13, 2014 THE LAWS OF MENDEL
  3. 3.  But his findings were discarded due to the prevailing theories of Evolution.  Later on, his theories were again discovered simultaneously by:  Hugo de Vries in Holland  Carl Correns in Germany  Eric von Tschermak in Austria ; in 1900. “FATHER OF GENETICS” September 13, 2014 THE LAWS OF MENDEL
  4. 4. WHY PEA PLANT…?? Flower structure of pea ensured self-pollination and also, well defined male and female parts. Single season crop. September 13, 2014 THE LAWS OF MENDEL
  5. 5. Emasculation and pollination of pea flowers is quite easy. September 13, 2014 THE LAWS OF MENDEL
  6. 6. reproduce sexually. In the varieties available, several characters had two contrasting forms, which were easily distinguishable from each other. September 13, 2014 THE LAWS OF MENDEL
  7. 7. HYPOTHETICO-DEDUCTIVE METHOD APPLIED BY MENDEL (APPARENTLY UNKNOWINGLY) Theory September 13, 2014 THE LAWS OF MENDEL
  8. 8. SEVEN PAIRS OF SIMPLE DIFFERENCES September 13, 2014 THE LAWS OF MENDEL
  9. 9. TERMINOLOGY • Character - morphological, anatomical or behavioral feature of an organism. • Allele - different alternative forms of gene ; e.g., a gene for height has two alleles: one for tall and one for dwarf. • Homozygous – An individual with two identical alleles. • Heterozygous - An individual with two different alleles. • Phenotype: observable characteristic of the some organism like color, size, form and structure Eg: tall, short • Genotype: genetic composition of an organism and cannot be seen Eg: TT, tt, Tt September 13, 2014 THE LAWS OF MENDEL
  10. 10. F1 generation : the hybrid offspring of the parental generation. F2 generation: the self fertilized progenies of F1 generation plants. Monohybrid cross: a cross between parents differing in only one trait or characters. Dihybrid cross: a cross between parents differing in two traits or characters. Test cross: a cross of F1 hybrid to recessive parent type. Back cross: the cross of F1 hybrid to one of parents. September 13, 2014 THE LAWS OF MENDEL
  11. 11. September 13, 2014 THE LAWS OF MENDEL
  12. 12. LAW OF DOMINANCE (GIVEN BY ERIC VON TSCHERMAK)  Every gene has two alleles that can code for a trait.  One allele is dominant, meaning it will always show.  One allele is recessive, meaning it will be masked by the presence of the dominant allele. Tall plant (TT) Dwarf plant (tt) F1 Tall plant (Tt) September 13, 2014 THE LAWS OF MENDEL
  13. 13. F1 Tall plant (Tt) F1 Tall plant (Tt) Tall plant (TT) Tall plant (Tt) Dwarf plant (tt) . . . . . . . However, this law was not fully accepted as due to : • co-dominance ; • incomplete dominance ; • over dominance. September 13, 2014 THE LAWS OF MENDEL
  14. 14. LAW OF SEGREGATION •During the formation of gametes, the paired alleles separate (segregate) randomly so that each gamete receives one allele or the other. •The two alleles of a gene present in the F1 do not contaminate each other; they separate and pass into different gametes in their original form producing two different types of gametes in equal proportion. September 13, 2014 THE LAWS OF MENDEL
  15. 15. •The pair of alleles of each parent separate and only one allele passes from each parent on to an offspring •Which allele in a parent's pair of alleles is inherited is a matter of chance •Segregation of alleles occurs during the process of gamete formation (meiosis) •Randomly unite at fertilization September 13, 2014 THE LAWS OF MENDEL
  16. 16.  Mendel experiment , he crossed tall and dwarf varieties of garden peas.  F1 produced were tall.  When F1 were self-fertilized, both tall and dwarf progenies were produced in F2 generation. 75% were tall and 25% were dwarf  An F2 of 1064, consisted of : 787 tall plants and 277 dwarfs: an almost 3:1. September 13, 2014 THE LAWS OF MENDEL
  17. 17.  When F1 plants from Mendel’s experiments were crossed back to the dwarf variety, half the progeny were tall and half dwarf.  The phenotypic ratio observed was 1:1.  This further demonstrated more conclusively the Principle of Segregation.
  18. 18. When a similar experiment was done with each pair of characters, the results were the same: September 13, 2014 THE LAWS OF MENDEL
  19. 19. LAW OF INDEPENDENT ASSORTMENT  This law states that member of different pairs of alleles assort independently during the formation of gametes.  This means that traits are transmitted to offspring independently of one another. September 13, 2014 THE LAWS OF MENDEL
  20. 20.  Mendel crossed plants that differ in two pairs of alleles. e.g., round green seeds and wrinkled yellow seeds.  F1 hybrids were round and yellow seeds, as expected.  When F1 were self-fertilized , four F2 phenotypes were observed.  From a total of 556 seeds, the following distribution :- 315 round green ; 108 round yellow ; 101 wrinkled green; and 32 wrinkled yellow.  This results closely fit a ratio of 9 : 3 : 3 : 1 . September 13, 2014 THE LAWS OF MENDEL
  21. 21. When Mendel crossed the F1 generation obtained with the recessive parent, four different phenotype were obtained. It verified the ratio in which the different gametes of the F1 hybrid were produced..
  22. 22. September 13, 2014 THE LAWS OF MENDEL
  23. 23. September 13, 2014 THE LAWS OF MENDEL
  24. 24. September 13, 2014 THE LAWS OF MENDEL
  25. 25. WHY WAS MENDEL SO SUCCESSFUL..?? Studied the inheritance of only one pair of contrasting characters at a time. Selected pea varieties that had clearly different forms of one or more characters, e.g., round and wrinkled seeds, yellow and green cotyledons, etc. Carried out his experiments with great care and elaborateness. September 13, 2014 THE LAWS OF MENDEL
  26. 26.  Accurate and incisive analysis of the reasons.  His knowledge of mathematics was a definite asset for the interpretation.  Classified all the plants of a population on the basis of contrasting characters under study. September 13, 2014 THE LAWS OF MENDEL
  27. 27. NEGLECTION OF MENDEL’S FINDING :  Using mathematical principles was something new and unacceptable to the biologists.  Studied contrasting pairs of characters exhibiting discontinuous variation unlike his contemporaries like Darwin, Galton and others.  The phenomena of fertilization and the behavior of chromosomes during cell divisions were not known at that time.  No further publishing of his work. September 13, 2014 THE LAWS OF MENDEL
  28. 28.  Studies of Mendel appeared to establish the constancy of characters of a species generation after generation, which was contrary to the theory of evolution at that time.  Mendel failed to demonstrated the validity of his conclusions in other species.  Mendel corresponded extensively with his contemporary, the noted botanist, Nageli. September 13, 2014 THE LAWS OF MENDEL
  29. 29. BIOLOGICAL SIGNIFICANCE OF MENDEL’S LAWS It showed the pattern of inheritance of the character from parent to the offsprings. The Law of Independent Assortment has laid the foundation of inheritance which claimed that differernt genes assorted themselves independently of one another during gamete formation and had established the relationship between dominant and recessive gene type. September 13, 2014 THE LAWS OF MENDEL
  30. 30.  It also provided the reason for variation in offspring transferred from the parents to the offspring in the form of gene (factor) present in chromosome of gamete.  The Law of Segregation ; according to this law, when an individual of a species mate, the copy of genes are separated and assorted so that each of gamete receive only one copy. By the discovery of meiosis, this notion was confirmed. September 13, 2014 THE LAWS OF MENDEL
  31. 31. “Genetics has moved far head than the protoidea that had been laid down by Mendel , but still the science owes its existence to the still the science owes its existence to the discovery & ideas that had originally been laid down Mendel.” September 13 2014 31 THE LAWS OF MENDEL
  • SazidHasan9

    Jun. 29, 2021
  • AkashManwar

    Jun. 7, 2021
  • AmitJakhal

    Apr. 20, 2021
  • DheerajJaiswar1

    Feb. 4, 2021
  • RamKumar2258

    Feb. 3, 2021
  • JyotiArya31

    Jan. 5, 2021
  • LakhvinderSingh67

    Dec. 24, 2020
  • KavyaraniRathod

    Dec. 1, 2020
  • Krishansharma151

    Sep. 24, 2020
  • Preethialphonsa

    Sep. 12, 2020
  • adanshah4

    Jun. 29, 2020
  • bhbhatt93

    Apr. 23, 2020
  • MelaniaRomero

    Mar. 27, 2020
  • SyraineMunez

    Mar. 17, 2020
  • nooralish786

    Feb. 21, 2020
  • ArpitanjaliBhoi

    Jan. 20, 2020
  • ushaswini_sunkara

    Dec. 4, 2019
  • SunilLakshman2

    Oct. 7, 2019
  • dralokkhare

    Sep. 25, 2019
  • BonySaikia

    Sep. 7, 2019

MENDEL'S LAWS AND THEIR IMPORTANCE

Views

Total views

30,675

On Slideshare

0

From embeds

0

Number of embeds

10

Actions

Downloads

1,165

Shares

0

Comments

0

Likes

43

×