Answer:
directional selection
Explanation:
The directional selection is a type of Darwinian selection where a particular phenotype is favored in the population, thereby modifying the allelic frequencies to increase the proportion of the favored phenotype. <em>Biston betularia</em>, also known as peppered moth, is a species that was influenced by directional selection in its recent past. Before the industrial revolution, the frequency of light-colored moths was predominant compared to the darker-colored phenotypes, because this color has higher adaptive fitness in a clean, no pollution environment, thereby light-colored moths were able to avoid predatory birds. However, during the industrial revolution, the frequency of dark-colored moths increased in response to pollution (i.e. darker environment), thereby conferring a higher adaptive fitness to darker phenotypes.
Answer:
In experimental animals, such as mice, rats, and dogs, DDT has shown to cause chronic effects on the nervous system, liver, kidneys, and immune system. It has also been found that humans, who were occupationally exposed to DDT, suffered chromosomal damage.
Explanation:
Answer:
As a plant's reproductive part, a flower contains a stamen (male flower part) or pistil (female flower part), or both, plus accessory parts like sepals, petals, and nectar glands (Figure 19). The stamen is that the male sex organ. It consists of a pollen sac (anther) and a protracted supporting filament.
Explanation:
