Which Population was Unaffected by Density-Dependent Factors

Question

Which population was unaffected by density-dependent factors?
A) elk in Yellowstone National Park in the 1970s
B) Norway lemmings
C) yeast that ferment grape juice into wine
D) bacteria kept in a culture that has its nutrients constantly replenished

Accepted Answer

Density-dependent factors are factors whose effects on the size or growth of the population vary with the population density. These include competition for resources, predation, disease, and migration. In the case of bacteria kept in a culture with constantly replenished nutrients, their population is not limited by density-dependent factors because their essential resources (nutrients) are always available, regardless of the population density.