Question

1. if a culture starts with 50 cells, how many cells will be present after five generations with no cell death? a. 200 b. 400 c. 1600 d. 3200 2. in which phase would you expect to observe the most endospores in a bacillus cell culture? a. death phase b. lag phase c. log phase d. log, lag, and death phases would all have roughly the same number of endospores.

Explanation:

1.

Step1: Identify the cell - growth formula

In binary fission (common cell - growth in many microorganisms), the number of cells \(N\) after \(n\) generations starting with an initial number of cells \(N_0\) is given by \(N = N_0\times2^n\).

Step2: Substitute the values

Here, \(N_0 = 50\) and \(n = 5\). So \(N=50\times2^5\).
First, calculate \(2^5=2\times2\times2\times2\times2 = 32\).
Then, \(N = 50\times32=1600\).

Endospores are formed by Bacillus cells as a survival mechanism in response to harsh conditions, which are most prevalent in the death - phase when nutrients are depleted and environmental stress is high.

Answer:

C. 1600
2.