You culture a plate of fibroblasts to perform some biocompatibility assays on chase-i-cillin. Your initial cell seeding is 50,000 cells, and you measure the number of cells at various points over the next few days: a. Plot the cell growth on semilog(y) axes. Label the different phases of the growth curve. b. What is the approximate lag time of these cells? c. What is the doubling time of these cells? (Note: doubling time is *not* affected by the time in the lag phase.) What is the tripling time?

5. A cultural experience (10 points) You culture a plate of fibroblasts to perform some biocompatibility assays on chase-i-cillin. Your initial cell seeding is 50,000 cells, and you measure the number of cells at various points over the next few days: Time (hours) 0 5 10 15 20 30 40 50 60 70 Cell Count 50000 52000 77600 115800 172800 384500 855800 984200 1033400 930000 a. Plot the cell growth on semilog(y) axes. Label the different phases of the growth curve. b. What is the approximate lag time of these cells? c. What is the doubling time of these cells? (Note: doubling time is *not* affected by the time in the lag phase.) What is the tripling time