Artificial selection Knowledge-Based Practice

Questions

1. 1.

   Which of the following observations provides the clearest evidence that artificial selection can produce substantial morphological divergence from a single ancestral lineage?

   • A) A bacterial culture develops resistance to an antibiotic following repeated exposures in a clinical setting.
   • B) Tomato plants grown in shaded environments develop significantly taller stems than genetically identical plants grown in direct sunlight.
   • C) Selective propagation of different structural parts of wild mustard (Brassica oleracea) gave rise to distinct vegetables such as cabbage, broccoli, and kale.
   • D) Mating between two distinct species of equines produces hybrid offspring that are completely sterile.
2. 2.

   Which of the following best explains why traits favored by artificial selection frequently decrease an organism's ability to survive in a natural, unmanaged habitat?

   • A) Domesticated organisms accumulate higher spontaneous mutation rates that inherently destabilize essential metabolic pathways.
   • B) Selected phenotypes prioritize human utility rather than reproductive and survival advantages in the wild.
   • C) Artificial selection prevents organisms from undergoing directional selection when environmental conditions change.
   • D) Intensive breeding completely replaces sexual reproduction with vegetative propagation, eliminating natural genetic recombination.
3. 3.

   Which condition must be present in a population for artificial selection to successfully alter the expression of a specific trait across successive generations?

   • A) Heritable genetic variation for the trait within the breeding population
   • B) High environmental stress that threatens organismal survival in the wild
   • C) Targeted novel mutations directly induced by the breeding process
   • D) Identical genetic backgrounds across all chosen breeding individuals
4. 4.

   Which of the following is a common long-term genetic consequence of intensive artificial selection in a domesticated population?

   • A) A marked reduction in overall genetic diversity and decreased survivability in natural environments
   • B) An increase in overall genetic diversity due to an elevated rate of beneficial mutations
   • C) An enhanced reproductive fitness when competing against wild species across diverse habitats
   • D) A complete elimination of deleterious recessive alleles from the population's gene pool
5. 5.

   Which of the following describes the primary factor that distinguishes artificial selection from natural selection?

   • A) Environmental pressures determine which individuals survive and reproduce.
   • B) Mutations are directly induced by climate fluctuations to create beneficial alleles.
   • C) Humans consciously choose which individuals reproduce based on specific desired traits.
   • D) Organisms deliberately alter their own genetic material to adapt to a changing habitat.

Answers and step-by-step solutions appear after you finish the test.