CLASS 10 SCIENCE - CHAPTER 8 NOTES
HEREDITY
======================================================================
==========
--------------------------------------------------------------------------------
PAGE 1: ACCUMULATION OF VARIATION & IMPORTANT TERMS
--------------------------------------------------------------------------------
[1.1] ACCUMULATION OF VARIATION DURING REPRODUCTION
* Heredity: Parents se unke bacchon (offsprings) mein characters ya traits ka
transfer hona Heredity kehta hai.
* Variation: Ek hi species ke alag-alag organisms ke beech jo jism (physical)
ya genetic antar (differences) hote hain, unhe Variation kehte hain.
* Variation ka Fayda: Asexual reproduction mein bohot kam variation hota hai,
lekin Sexual reproduction mein bohot zyada variation hota hai. Yeh variation
species ko badalte environment mein zinda (survive) rakhne mein madad karta hai.
[1.2] IMPORTANT TERMS (Zaroori Shabd)
1. Gene: Yeh DNA ka ek chhota sa tukda (section) hota hai jo kisi ek specific
character (jaise skin color ya height) ko control karta hai.
2. Alleles: Ek hi gene ke do alag-alag roop (variants).
* Example: Tallness ke liye 'T' aur Dwarfness ke liye 't'.
3. Dominant Trait: Wo character jo hamesha agli peedhi (generation) mein saaf
dikhayi deta hai, chahe single allele ho (jaise 'T' in Tt).
4. Recessive Trait: Wo character jo sirf tabhi dikhta hai jab dono alleles
same hon (jaise 'tt' in dwarf plant). It hides in the presence of a dominant trait.
5. Genotype: Kisi organism ka genetic structure (jaise TT, Tt ya tt).
6. Phenotype: Organism ka bahari roop jo aankhon se dikhta hai (jaise Tall ya Short).
--------------------------------------------------------------------------------
PAGE 2: MENDEL'S EXPERIMENT (MONOHYBRID CROSS)
--------------------------------------------------------------------------------
[2.1] GREGOR JOHANN MENDEL (Father of Genetics)
* Mendel ne inheritance ke niyam diye. Unhone apne experiment ke liye
**Garden Pea (Pisum sativum)** yaani matar ke paudhe ko chuna.
* Matar ke paudhe ko chunne ke karan:
1. Isme saaf-saaf dikhne waale contrasting characters (jaise Tall/Short, Round/Wrinkled
seed) hote hain.
2. Iska life span chhota hota hai.
3. Isme self-pollination aur cross-pollination dono aasani se karaya ja sakta hai.
[2.2] MONOHYBRID CROSS (Ek character ka cross)
Jab Mendel ne ek pure Tall (TT) aur ek pure Dwarf (tt) matar ke paudhe ka cross karaya:
* F1 Generation (Pehli Peedhi): Saare paudhe Tall (Tt) paida hue. Isse pata chala
HEREDITY
======================================================================
==========
--------------------------------------------------------------------------------
PAGE 1: ACCUMULATION OF VARIATION & IMPORTANT TERMS
--------------------------------------------------------------------------------
[1.1] ACCUMULATION OF VARIATION DURING REPRODUCTION
* Heredity: Parents se unke bacchon (offsprings) mein characters ya traits ka
transfer hona Heredity kehta hai.
* Variation: Ek hi species ke alag-alag organisms ke beech jo jism (physical)
ya genetic antar (differences) hote hain, unhe Variation kehte hain.
* Variation ka Fayda: Asexual reproduction mein bohot kam variation hota hai,
lekin Sexual reproduction mein bohot zyada variation hota hai. Yeh variation
species ko badalte environment mein zinda (survive) rakhne mein madad karta hai.
[1.2] IMPORTANT TERMS (Zaroori Shabd)
1. Gene: Yeh DNA ka ek chhota sa tukda (section) hota hai jo kisi ek specific
character (jaise skin color ya height) ko control karta hai.
2. Alleles: Ek hi gene ke do alag-alag roop (variants).
* Example: Tallness ke liye 'T' aur Dwarfness ke liye 't'.
3. Dominant Trait: Wo character jo hamesha agli peedhi (generation) mein saaf
dikhayi deta hai, chahe single allele ho (jaise 'T' in Tt).
4. Recessive Trait: Wo character jo sirf tabhi dikhta hai jab dono alleles
same hon (jaise 'tt' in dwarf plant). It hides in the presence of a dominant trait.
5. Genotype: Kisi organism ka genetic structure (jaise TT, Tt ya tt).
6. Phenotype: Organism ka bahari roop jo aankhon se dikhta hai (jaise Tall ya Short).
--------------------------------------------------------------------------------
PAGE 2: MENDEL'S EXPERIMENT (MONOHYBRID CROSS)
--------------------------------------------------------------------------------
[2.1] GREGOR JOHANN MENDEL (Father of Genetics)
* Mendel ne inheritance ke niyam diye. Unhone apne experiment ke liye
**Garden Pea (Pisum sativum)** yaani matar ke paudhe ko chuna.
* Matar ke paudhe ko chunne ke karan:
1. Isme saaf-saaf dikhne waale contrasting characters (jaise Tall/Short, Round/Wrinkled
seed) hote hain.
2. Iska life span chhota hota hai.
3. Isme self-pollination aur cross-pollination dono aasani se karaya ja sakta hai.
[2.2] MONOHYBRID CROSS (Ek character ka cross)
Jab Mendel ne ek pure Tall (TT) aur ek pure Dwarf (tt) matar ke paudhe ka cross karaya:
* F1 Generation (Pehli Peedhi): Saare paudhe Tall (Tt) paida hue. Isse pata chala
