1. OK OK OK TOKEY

2. CRABPRESERVATION

3. GRAPH HAI YHA
 Keep on it

4. CRABPRESERVATION
⚫FirstdocumentedbyBoyle(1663).
⚫Firstconceptofspermpreservationby
Lazzarospallanzini(1760).
⚫ Most significantdiscoverywastheuseof
glycerolascryoprotectant byPolgeand
smith(1949)

5. PRINCIPLE
1. FREEZING
2. STORING
3. THAWING

6. CONT
..
⚫ Theabilityofglycerol toprotectcellsfromfreezing
injurywasdiscoveredaccidentally
.
⚫ Thesubsequentdevelopmentof
CRABPRESERVATION techniqueshashad ahuge
impactinmanyfields, mostnotablyin
reproductivemedicine.
⚫ OK Lets do it
⚫

7. ⚫ Freezing injuryhasbeenshownto havetwo
components,direct damage fromtheicecrystals
andsecondarydamage causedbytheincreasein
concentrationofsolutesasprogressivelymoreiceis
formed.
⚫ Intracellularfreezingisgenerallylethalbutcanbe
avoided bysufficientlyslow cooling, and under
usualconditionssolutedamagedominates.

8. BAS CHAL RHA H

9. TUSSI BATAO