Question

model 3 - growth curves
diagram a - exponential growth curve
diagram b - logistic growth curve

1. refer to model 3.

a. during what phase of the growth curves in each diagram is the population just beginning to colonize an area?
b. which type of population growth appears to continue unchecked?

1. the growth curves in model 3 are often referred to using the letters of the alphabet they resemble. the logistic growth curve is sometimes referred to as an s - curve. what letter would you use to describe the exponential growth curve?
2. what causes the population to slow down during logistic growth?
3. the maximum population an environment can sustain is affected by environmental factors that cause the population to level out or become stable. what term is used to describe this level of logistic growth?
4. propose some reasons why population growth is so rapid immediately after the lag phase in both diagrams of model 3?
5. exponential growth (diagram a) refers to the phenomena of populations that double in size every generation. if you start with a single bacterium capable of dividing every 20 minutes, how many bacteria would you have after just four hours?

Explanation:

Step1: Calculate the number of 20 - minute intervals in 4 hours

Since 1 hour has 60 minutes, 4 hours have \(4\times60 = 240\) minutes. The number of 20 - minute intervals \(n=\frac{240}{20}=12\)

Step2: Use the exponential growth formula \(N = N_0\times2^n\)

Here, \(N_0 = 1\) (the initial number of bacteria), and \(n = 12\). So \(N=1\times2^{12}\)

$$2^{12}=4096$$

Answer:

4096