Objectives::

- We want to prove the existence of a genetic inheritance in all the alive beings

- We search to know if the genetic inheritance is identical at all the species.

- We search to know if the genetic inheritance is transmissible in experiments of a species to another.

Does there exist a genetic material in all the alive

beings? We wants to extract from the DNA of different cellular

species such as:

- Plant species : the onion - Animal species eukaryote* pluricellular : saliva - Animal species eukaryote* pluricellular : liver of mouse - Animal species prokaryote** : bacterium

*: cell :containing a core **: cell: not having a core

Material

DNA human

DNA of onion

DNA of liver

DNA of bacterium

- Saliva- test tube of 15 ml - Plug ( TE*+SDS+Na Cl)- Alcohol (ethanol)

-Onion- test tube of 50ml- Plug (TE*+SDS+Na Cl)- A centrifuge-Alcohol (ethanol)

-A lump of liver (2g)- a Potter- Tube of 50 ml- Plug (TE*+SDS+NaCl)-Alcohol (ethanol)

-Bacterium- a centrifuge- Streamroom- culture medium- Plug ( TE*+ SDS+NaCl) -Alcohol (ethanol)

*: Plug Tris-EDTA, pH 8

Procedure of extraction of DNA of liver

• LIVER:

• Chop a liver

• Put in a potter and crush

• Put in a plug (SDS+NaCl+ TE) to make burst the cells.

• Centrifuge

• To eliminate the supernatant

• Add the ethanol

• Recover the ball supposed to be DNA

Procedure of extraction of DNA of bacterium

• BACTERIUM:

• Setting in culture of the bacterium

• Put in a tube eppendorf

• Centrifuge

• Eliminate the culture medium

• Put in the plug (SDS+NaCl+TE)

• Agitate after add ethanol

• Put in the refrigerator

• Recover the ball supposed to be DNA

Procedure of extraction of DNA of human saliva

HUMAN SALIVA:

• Collect human saliva • Pour in a tube of 15ml

• Pour the plug (SDS +NaCl+TE) in this tube

• Pour ethanol• Let rest

• Recover the ball

supposed to be DNA Ball of DNA

Procedure of extraction of DNA of onion

• ONION

• Chop the onion

• Put in a tube of 50mL

• Put in the plug (SDS+NaCl+TE)

• Centrifuge

• Add the ethanol

• recover the ball supposed to be DNA

First objective’s conclusion :

We observe a ball, that supposing to us to be DNA, in the four tubes of the various cellular species. If that is checked, we can highlight a genetic inheritance in the alive beings tested.

Test of characterization of the DNA

Thanks to the composition of the DNA that we know, we carried out, in class, an experiment aiming at proving the presence of the various elements composing the DNA. A coloring specific to the DNA consolidated us in our idea that the collected ball was well of the DNA.

Is the genetic inheritance identical between species?

• One treats the DNA with the protein K "to degrade" proteins related to the DNA. A fraction of this DNA was treated with enzymes of restriction.

1 MARKER OF SIZE

2 DNA OF LIVER

3 DNA OF BACTERIE

4 ONION DNA

5 DNA OF SALIVA

6 DNA OF LIVER DIGESTED

7 DNA OF BACTERIE DIGESTED

8 ONION DNA DIGESTED

9 DNA OF SALIVA DIGESTED

1 2 3 4 5 6 7 98

Analyze by electrophoresis on GEL of agar of DNAs extracted

Second objective’s conclusion:

• One observed thanks to the technique of electrophoresis that between the species tested the genetic inheritance was not identical because the migrations of the DNA of each species were not the same ones.

Can one transmit the genetic inheritance of one species to

the other?• MATERIALS:

• Bacteria • - DNA coding the GFP (Fluorescent Green Protein)

taken with the jellyfish • - box of Petri containing agar• - Plasmid (circular DNA) • - Starters • - Taq DNA Polymerase • - DNTP • - Plug for PCR • - Thermocyclor• - Tubes of PCR

Technique of the PCRTechnique of the PCR

Denaturising ofDenaturising of the DNAthe DNA

Séquence cibleGFP

HybridizingHybridizing

ElongationElongation

Cycle 1Cycle 1

Cycle 2 Cycle 2

Cycle 3Cycle 3

We have to carry out 29 cycles

TRANSFER OF THE GENE OF GFP RESULTING FROM MEDUSE TO THE

BACTERIE (Escherichia Coli)

GFP

Plasmid

Transformation (introduction of the plasmid)Bacteri

a

Transformed bacterium (GMO)

Obtaining genetically modified bacteria: fluorescence GFP

Genetically modified bacteria

Bacteria (control)

General conclusion

We have to carry out three experiments aiming at proving the existence of the DNA in all the species.

We have deduce the existence from the DNA, its authenticity between the species and the possibility of transmission of the genetic information from one species to another in laboratory.

Au vue des résultats de nos expériences, nous pouvons déduire qu’ il existe effectivement un patrimoine génétique chez tous les êtres vivants testés.