is life one and undivided ? -is cellular division common to all living beings ? -do divisions...
DESCRIPTION
It is thought that there is a division of cells in all living beings responsible the unity of life : For that we have counted the number of animal, vegetable and bacterial cells there are before and after setting them in a culture.TRANSCRIPT
![Page 1: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/1.jpg)
Is life one and undivided ?
-Is cellular division common to all living beings ?
-Do divisions proceed in the same way?
![Page 2: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/2.jpg)
Is cellular division common to all living beings ?
![Page 3: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/3.jpg)
It is thought that there is a division of cells in all living beings responsible the unity of life :
For that we have counted the number of animal, vegetable and bacterial cells there are before and after setting them in a culture.
![Page 4: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/4.jpg)
Material and methods- optical Microscope and the cell of
Malassez allows us to observe unicellular animal cells: vegetable yeasts and cells
- Spectrophotometer and absorbance (bacterial cells too small to be seen with the optical microscope=>indirect technical use)
- MTT colorimetry test on the plate reader and (use for pluricellular animal cells: lymphocytes)
![Page 5: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/5.jpg)
Optical microscope and counting of the cells on a Malassez slide
![Page 6: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/6.jpg)
Preparation of the nutrient necessary to yeast
Starch is the nutrient necessary to the development of yeast. We want to know what
the concentration is for an optimal developement.1/10 1/10 1/10Dilution
![Page 7: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/7.jpg)
Culture of yeastsIncubation of yeast in the
previous tubes of culture The tubes are then left in an incubator for 24 Hours
![Page 8: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/8.jpg)
Incubator
The incubator makes it possible to maintain the cells moving at the right temperature needed for their survival
![Page 9: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/9.jpg)
Resultswater+yeast
Without starch
water+yeast
Starch 0,0001g/ml
water+yeast
Starch 0,001g/ml
water+yeast starch 0,01g/ml
A t0(en cell/mL)
6,00E+07 3,10E+07 3,30E+07 3,60E+07
At24(en cell/mL)
2,10E+08 1,20E+08 1,7E+08 3,00E+08
Cell multiplication factor
3.5 3.9 5.2 8.3
The richer the culture medium is, the higher is the multiplication of cells
![Page 10: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/10.jpg)
Bacteria 1) Comparison of the growth of
bacteria in rich or poor culture medium
2) Analysis with a spectrophotometer3) Absorbance 60 times higher in a
rich culture medium Conclusion: need for a culture
medium rich in nutrients is required.
![Page 11: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/11.jpg)
The spectrophotometer and absorbance
The absorbance of the solution is measured with a laser.This absorbance is proportional to the cell concentration of the sample
![Page 12: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/12.jpg)
Analysis of animal cells multiplication using colorimetric test
Principle : Study of 2 culture mediums, one rich in nutrients in presence of FCS (fœtal calf serum) and one poor in nutrients.
Colorimetric test:Test based on the activity of the protein MTT: coloration by MTT increases with cell concentration.
1/Wavelenght 620nm. The absorbance is proportional to the cell concentration
2/Tracing of the calibration line3/Measurement of the absorbance of the different cell
culture concentrations from the calibration line .
Colorimetric test example
Calibriing well
6 wells containing the rich medium
6 wells containing the poor medium
![Page 13: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/13.jpg)
Animal cells : colorimetric test
y = 535678x - 19893R2 = 0,9691
0,00E+00
1,00E+05
2,00E+05
3,00E+05
4,00E+05
5,00E+05
6,00E+05
0 0,2 0,4 0,6 0,8 1
absorbance
nom
bre
de c
ellu
les
![Page 14: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/14.jpg)
The animal cells Sample 1 Sample 2 Sample 3 Average
Standart Deviation
+ FCS* 121525 127954 152056 133845 16095
+FCS 153663 45992 149381 116345 60965
-FCS 118311 53493 84028 85277 32427
-FCS 99027 60458 82421 80635 19346
0,E+00
2,E+04
4,E+04
6,E+04
8,E+04
1,E+05
1,E+05
1,E+05
2,E+05
2,E+05
2,E+05
+ FCS +FCS -FCS -FCS
Cel
l num
ber
•Foetal
•Calf•Serum
The number of cells decreases in poor culture medium
![Page 15: Is life one and undivided ? -Is cellular division common to all living beings ? -Do divisions proceed in the same way?](https://reader035.vdocuments.mx/reader035/viewer/2022062401/5a4d1b047f8b9ab059987ee4/html5/thumbnails/15.jpg)
Conclusion
1/Presence of a cellular division in all living beings 2/Division in all living beings requires nutrients