Cryopreservation

Cryopreservation of animal cells is important. Which of the following is LEAST likely the reason?

• animal cells can change over time

• all passage numbers of a cell line can be frozen and studied

• well maintained cell seed stocks are critical to reproducibility

• it provides a back-up if your cells get contaminated or die by accident

In which phase of the growth curve that the cells should be cryopreserved?

• lag phase

• log phase

• stationary phase

• decline phase

Heteroploid cell lines are easier to preserve than primary and diploid cells.

• True

• False

Which of the following is LEAST likely to affect the process of freezing cells?

• Temperature

• Freezing medium formulation

• Cell density

• Gas exchange

When freezing cells, it is best to have cells that are

• low passage and well fed cells

• resistant to high-speed centrifugation

• high passage and un-fed cells

• low viability cells

Role of DMSO in the freezing media is to minimize cell damage due to contamination.

• True

• False

In the cryopreservation process, cells are more viable with slow freezing rate.

• True

• False

This material is always required for freezing cell process.

• True

• False

 If you want to store your cell line for more than three years, which condition will you use to keep the cells?

• On dry ice

• In fridge (-20 degree Celsius)

• In freezer (-70 degree Celsius)

• In liquid nitrogen

From our experiment, which flask would you expect to have the highest number of cell survival once they are thawed?

• With DMSO, stored at -70^oC

• Without DMSO, stored at -70^oC

• With DMSO, stored in liquid nitrogen

• Without DMSO, stored in liquid nitrogen