Biotechnology Principles and Processes Class 12th Chapter 9 Notes PDF NEET 2027 + PYQ

Hello friend,

I am NEET Dropper, today I'm sharing complete notes *Chapter 9: Biotechnology - Principles and Processes* 🧬

* SHORT NOTES.   NEET 2027*

*Note*: New NCERT ✅

### *1. BIOTECHNOLOGY KE 2 CORE PRINCIPLES*

1. *Genetic Engineering* = Gene ko modify karke host me daalna taaki naya product bane

2. *Bioprocess Engineering* = Microbes/cells ko sterile condition me large scale pe grow karna

*rDNA Technology ke 3 Steps*:

1. Identification of DNA with desirable gene

2. Introduction of rDNA into host

3. Maintenance of introduced DNA + Gene expression

### *2. TOOLS OF rDNA TECHNOLOGY* 🔧

#### *A) Restriction Enzymes = Molecular Scissors* ✂️

*Kaam*: DNA ko specific jagah pe cut karte hain

*Ex*: _EcoRI_ = _E.coli_ RY13 strain se

*Diagram: EcoRI ka Action*

5'---G AATTC---3' 5'---G AATTC---3'

3'---CTTAA G---5' → 3'---CTTAA G---5'

     ↑ EcoRI site Sticky ends ban gaye

*Palindromic Sequence*: 5'-GAATTC-3' | 3'-CTTAAG-5' → Dono side same padha jaata hai

*Sticky ends* = Overhang wale ends, easily join ho jaate hain

*DNA Ligase* = Molecular glue, phosphodiester bond banata hai

#### *B) Cloning Vectors = Gene Taxi* 🚗

*Properties*:

1. *ori* = Origin of replication → Copy number control

2. *Selectable marker* = amp^R, tet^R → Transformants select karne ke liye

3. *Cloning sites* = Unique restriction sites

4. *Insertional inactivation* = Foreign DNA daalne se marker gene band ho jaata hai

*Diagram: pBR322 Plasmid*

        [ori]

         |

amp^R --[ ]-- tet^R

         |

   BamHI, SalI, PvuI, PstI = Cloning sites

*Blue-White Selection*: β-galactosidase gene me insert → Recombinant = White, Non-recombinant = Blue

*Imp Vectors*:

1. *Ti plasmid* = _Agrobacterium tumefaciens_ → Dicot plants me gene transfer. Natural genetic engineer

2. *Retrovirus* = Animals me gene transfer, disarmed

#### *C) Competent Host Banana*

Bacteria apne aap DNA nahi leti. Isliye:

1. *CaCl2 + Heat shock 42°C* → DNA enters _E.coli_

2. *Microinjection* = Direct nucleus me - Animal cells

3. *Gene gun/Biolistic* = Gold/Tungsten particles + DNA - Plant cells

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### *3. rDNA TECHNOLOGY KE STEPS*

#### *Step 1: DNA Isolation*

Cell lyse karo →

*Lysozyme* = Bacteria | *Cellulase* = Plant | *Chitinase* = Fungus

RNA hatane = *Ribonuclease* | Protein hatane = *Protease*

DNA precipitate = Chilled ethanol

#### *Step 2: Gel Electrophoresis*

*Diagram*:

- Wells → DNA load

   ↓ Electric field

+ DNA fragments separate → Small = fast, Large = slow

   ↓ Ethidium bromide stain → UV me orange bands

*Elution* = Gel se DNA nikaalna

#### *Step 3: PCR = Polymerase Chain Reaction* 🔥

*Inventor*: Kary Mullis | *Enzyme*: *Taq polymerase* = _Thermus aquaticus_, heat stable

*Diagram: PCR Cycle*

1. Denaturation 94°C → dsDNA → ssDNA → 30 sec

2. Annealing 54°C → Primers bind → 1 min

3. Extension 72°C → Taq polymerase → New DNA → 2 min

Repeat 30 cycles → 1 billion copies

#### *Step 4: rDNA ko Host me Daalna*

Vector + Foreign DNA → Ligase → rDNA → Transformation into host

#### *Step 5: Recombinant Protein Banana*

*Bioreactor* = 100-1000L tank, large scale production

*Diagram: Stirred Tank Bioreactor*

   [Motor] → Agitator/Stirrer

      |

   Sampling port | O2 delivery | Foam breaker | pH control

      | | | |

   [________Culture Medium + Microbes________]

   [Temperature control system]

   [Drain]

*Batch vs Continuous*: Continuous me product nikaalte raho, medium daalte raho

*Downstream Processing* = Purification → Formulation → Quality check → Clinical trials

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### *NEET PYQ GOLDEN POINTS* 💯

1. *EcoRI* = 5'-GAATTC-3', Sticky end, _E.coli_ RY13

2. *Taq polymerase* = PCR, 72°C pe kaam karta hai, _Thermus aquaticus_

3. *pBR322* = amp^R + tet^R, rop gene, 1st artificial cloning vector

4. *Ti plasmid* = _Agrobacterium_, T-DNA, Dicot plants

5. *Insertional inactivation* = Select recombinants, Blue-white selection

6. *Bioreactor* = Large scale, NOT small scale lab

7. *Lysozyme* = Bacterial wall, *Chitinase* = Fungal wall

8. *Ethidium bromide* = DNA stain, UV me orange

9. *Microinjection* = Animals, *Gene gun* = Plants

10. *Selectable marker* = Antibiotic resistance gene

*1-Trick to remember minutes*:

*Scissor* = EcoRI-Palindrome | *Glue* = Ligase | *Xerox* = PCR-Taq-3step

*Taxi* = pBR322-ori-amp-tet | *Factory* = Bioreactor-1000L | *Plant wala* = Ti-Agrobacterium