How do you know if you have a ‘countable’ plate when doing a dilution series?   Two plates received 0.1 mL of the same dilution tube. The first has 293 colonies and the second has 158 colonies. Suggest a reasonable reason why this happened.

A.Why do you plate the cells from the viable count on LB agar without ampicillin? B.If you observe 100 colonies on your 1/100 plate, how many colonies do you expect if everything works perfectly on your 1/1000 plate?

1. A bacterial culture was grown for 12 hours. At 4-hour interval, the culture was sampled to determine the population ofthe culture, by transferring 25 mlof the suspension to 225 ml 0.90% NaCl. Three consecutive dilutions were further made by using 1 mlaliquot in 9 mlof 0.90% NaCl. One ml from each dilution was plated in each of duplicate plates. The following table shows the results of the plating method. EDI Sampling COUNTS 1st dilution 54; 61 TNTC 2nd dilution 3; 7 TNCT TNTC 3rd dilution 0; 0 242; 233 TNTC 4th dilution 0, 0 28: 37 249;246 1st 2nd 3rd TNTC * TNTC = Too numerous to count i. Determine the bacterial count (CFU/ml) every 4 hours of incubation for 12 hours. Show all computations. a. 1s* Sampling b. 2d Sampling c. 3* Sampling

A 5mL sample diluted 1:1 with trypan blue is counted using a hemocytometer. A total of 325 viable cells and 52 dead cells were counted in the four corner square and the big central square of the meter. What is the total number of dead cells per mL of the sample?

A 7 year old female patient is admitted to a local hospital for a greenstick radius break.  The break is repaired, the patient is sent home and receives a cast a few days later.  The patient arrives back at the hospital 20 days afterwards complaining of pain, sweeling under the cast.  Upon removal of the cast, there is notable swelling, pus, and a furuncle. a.  what type of specimen should you collect? b. What type of instant test would you perform? c. if your clinic ran out of the instant tests, what lower cost method would you use to identify the species? d. What would be the typical course of treatment? e. Due to some cases of antibiotic resistant infections at the same hospital, the doctors want to use a specimen and test for antibiotic resistence, What test would you perform, and which antibiotics should the doctor avoid prescribing?

You counted 4, 6, 12, 3 cells in each of the 4.outed squares of a hemacytomeyer. What are the cells per milliliter in that culture? If you resuspended your cell pellet 2.5 mL, what is the total cell count? How many uL do you need to add to a new culture if you want 4250 cells?

If you plated 0.1mL of a 103 dilution and you obtained 235 colonies on your agar plate, how many CFUs per mL were in your original sample? If a bacterium can divide once an hour, then after 5 hours, 1 bacterium will have yielded ______ bacteria