Color in peppered moths is controlled by genes. a light-colored variety and a dark-colored variety of a peppered moth species ex
ist in nature. the moths often rest on tree trunks, and several different species of birds are predators of this moth. before industrialization in england, the light-colored variety was much more abundant than the dark-colored variety and evidence indicates that many tree trunks at that time were covered with light-colored lichens. later, industrialization developed and brought pollution which killed the lichens leaving the tree trunks covered with dark
1. The reason why the dark-colored variety was in greater numbers present in the polluted environment is that the dark-colored moths were better adapted to the environment. The pollution killed the lichens which caused the tree trunks to have a much darker color than before. The dark color of the tree trunks permitted the dark-colored moths to hide and camouflage from the predators. That is why the dark-colored moths were better adapted to the polluted environment.
2. There could be many reasons why the light-colored variety was not completely eliminated from the polluted environment. The light-colored variety could be less effectively adapted to the polluted environment, but it wasn't completely extinct. This is because the light-colored moths could be resting and hiding in other places and not on the tree trunk. Also, some of the light-colored moths found in the polluted environment could have migrated from other less polluted places. Finally, some of the dark-colored moths could be carrying the allele for the light color.
3. The air pollution control laws could help reverse the environmental destruction caused by the industrialization. This could help in significantly decreasing the air pollution and restoring the balance of the ecosystem. If the pollution decreases, the population of lichens could recover and the tree trunks could be covered again with lichens. This, in turn, would make the color of the tree trunks lighter and the light-colored moths could hide and camouflage on the tree trunks again.
4. The diagram shows the percentage of each moth variety in the two different environments, the polluted and the non-polluted environment. The percentage of dark-colored moths in the non-polluted environment was closest to 15% and in the polluted environment, it nearly rose to 70%. The percentage of the light-colored moths in the non-polluted environment was nearly 85% and in the polluted environment it was closest to 24%.
5. The correct answer is "a given trait can be a favorable adaptation in one environment, but not in another environment". An evolutionary adaptation is a term referring to the characteristics of an organism which help him survive in a specific environment. If the environmental conditions change, the characteristics which were once favorable may no longer be. This is what all the above information shows; any change in the environment can make a once favorable adaptation disadvantageous.
The nucleus of the cell directs cell activity and acts like the control center. This is the place where gene activity is controlled in terms of the replication of the genes. In addition the movement and actions of the cell are also dictated from the nucleus.
Excretion is a process by which metabolic waste is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin. This is in contrast with secretion, where the substance may have specific tasks after leaving the cell. Excretion is an essential process in all forms of life.
There are three ways in which exogenous dna can be
introduced into a bacterial genome. These are; transduction, transformation and
conjugation. Transduction is the introduction of exogenous material into bacteria
by viruses; conjugation is exchange of genetic material between bacteria sexual
through reproduction; while transformation
is uptake of exogenous dna by bacteria, from its surrounding, through the
bacterial membrane.
