Practice Questions

TLS Online TPP Program

#Question id: 12000

The graph below shows the growth rates of populations of bacteria that have evolved for many generations at different culture temperatures (25°C, 30°C, and 35°C). Each population grows over only a limited range of temperatures (its thermal niche), which are bounded by its critical thermal limits. Within this range, growth rate increases with temperature up to a maximal value and then declines rapidly with increasing temperature. Growth rates are known to be the major determinant of fitness for these bacteria.
Which of the following is true concerning the thermal dependence of growth rate between 25°C and 30°C in these populations?

#Unit 10. Ecological Principles

Thermal dependence is greatest in the population evolved at 25°C.
Thermal dependence is greatest in the population evolved at 30°C.
Thermal dependence is greatest in the population evolved at 35°C.
Growth rates of all populations are equally thermally dependent over this temperature range.