Question

Under ideal conditions, an E. coli bacteria cell doubles every 20 minutes. The following graph represents an E. coli population, where x shows the time and y shows the number of bacteria cells in the population. Five stages of the bacteria's growth are marked on the graph. Select the true statement about the graph. A. The population grows at the same rate at stages B and C. B. The population grows at the slowest rate at stage A. C. The population grows more quickly at stage D than at stage E. D. The population grows at the fastest rate at stage D.

Answer 1

Answer: B

Step-by-step explanation:

the average rate of change is the same as slope (m). Calculate the slope between the beginning and ending coordinates for each stage.

A = (0, 1) → (4, 2.5)

           B = (4, 2.5) → (6, 4)

                           C = (6, 4) → (8, 6)

                                        D = (8, 6) → (10, 9)

                                                      E = (10, 9) → (12, 14)

$\frac{y _{2} - y_{1}} {x _{2} - x_{1}}$

Stage A

  $\frac{2.5 - 1}{4 - 0}$

= $\frac{1.5}{4}$

= 0.375

Stage B

  $\frac{4 - 2.5}{6 - 4}$

= $\frac{1.5}{2}$

= 0.75

Stage C

  $\frac{6 - 4}{8 - 6}$

= $\frac{2}{2}$

= 1.00

Stage D

  $\frac{9 - 6}{10 - 8}$

= $\frac{3}{2}$

= 1.5

Stage E

  $\frac{14 - 9}{12 - 10}$

= $\frac{5}{2}$

= 2.5

(A) Stage B = Stage C            False

(B) Stage A is the slowest      TRUE

(C) Stage D > Stage E             False

(D) Stage D is the fastest        False