Reference no: EM132352559

Some Virology Research Labs use Baby Hamster Kidney Cells (BHK Cells) to grow Mammalian Viruses in vitro.

The Cells will grow as a Monolayer attached to the Collagen-Coated Bottom of a 75 cm2 Flask (a 75 cm2 Flask usually contains approximately 15 ml of Growth Medium). To "split' a 75 cm2 Flask (i.e. transfer a small Amount of Cells from the original 75 cm2 Flask to several new 75 cm2 Flasks) you need to determine the Total Number of Cells in the original 75 cm2 Flask.

• You remove all Media from the Flask and wash the Cell Monolayer attached to the Bottom of the Flask with 10 ml Phosphate Buffered Saline (PBS). You decant ("pour-off") all of this PBS.
• You add 5.0 ml of Trypsin-EDTA to the Monolayer and incubate the Flask for approximately 5 Minutes at 37°C. The Enzyme Trypsin and the Detergent EDTA will loosen and remove the BHK Cells from the Bottom of the Flask. You do not decant the Trypsin-EDTA.
• You add 5.0 ml of Medium and transfer this Suspension of BHK Cells (now approximately 10 ml Total) to a 15 ml Conical Centrifuge Tube (just like the Green Cap Tube for the Hamburger Sample in Lab 6).
• You vortex this Conical Centrifuge Tube and use a Microtiter Pipette to load a 5μl Sample of this Cell Suspension into a Hemocytometer.

Almost all Hemocytometers on this Planet are identical to the ones we use in MIC 101. Hemocytometers have two (2) Counting Chambers, each of which is divided (like "Hollywood Squares") into Nine (9) Large Squares (1.0 mm x 1.0 mm). The Central Large Square is subdivided into 25 Medium Squares (0.2 mm x 0.2 mm)

You count the Cells in five (5) of the Medium Squares. -

Your Counts are: 44, 39, 34, 46 and 37

Approximately what was the Total Number of BHK Cells in the original 75 cm2 Flask?