Biology Key Questions Complete Full Unit Essay

The stated intent of the voyage was to obtain evidence to support the biblical theory of creation. The ultimate significance of the Journey was Darning’s observations and evidence that species do change over time and from place to place. 2. Most organisms might die because they are not resistant to the antibiotics. Some organisms can have traits that are resistant to antibiotics. The traits that help them survive are passed on to their offspring. This will change the population over time.

May cause the new population to not look like the ancestors. . Charles Lye’s book, Principles of Geology, profoundly influenced Darwin. Lye offered not Just a new geology but a new way of understanding nature. Lye showed how tiny, slow, gradual and cumulative change over immense periods of time could produce large changes. Natural, visible, causes should be sought to explain natural phenomenon. This view was known as unfamiliarity’s contrasted to more exciting scenarios requiring plenty of enormous catastrophe’s.

Darwin had the opportunity to witness all of these forces, such as erosion, earthquakes and volcanoes, during the Beagle voyage and he came convinced that Lye’s views were correct. Darwin made several very important discoveries about the geology of South America, volcanic islands and the origins of coral reefs by building on Lye’s ideas. 4. Within a given population exist genetic variations that may or may not make an individual more adapted to the environment or, more importantly, changes in the environment.

A species with the greatest amount of genetic variability is more likely to survive in a changing environment than a species that is limited. 5. Variation within population, differences o matter how small can potentially affect an individuals survival and/or reproductive success. Struggle for existence, this means individuals within a species regularly compete to obtain food, shelter and other necessities but not all of them will succeed. Descent with modification, the necessity of the most fit and adaptable individuals being able to pass their adaptations on to their offspring. . Cold tolerance could save entire crops from early or unseasonably cold weather. This is accomplished by scientists introducing a gene from cold water fish into plants such s tobacco and potatoes effectively making them resistant to cold spells. Gene transfer to non-target species could be a disadvantage if GEM plants interbreed with wild weeds making them herbicide tolerant as well and might start growing out of control. 7. Those giraffes with shorter necks couldn’t reach high enough get food to eat, so they died off before reproducing.

Those with longer necks that were able to reach the leaves and get the food were able to survive and reproduce. 8. A) When population sizes are very small, especially under a few hundred drift can cause large charges to allele frequencies over time leading to lose of genetic variation. B) Drift is most likely to occur to species that are geographically isolated or confined and have a small population, especially if less then a few hundred. C) It would be an example of the founder effect because the new bird colony originated from only a small amount of birds from the original much larger colony.

The new colony would also be/snow the detect tot inbreeding. 9 Genetic mutation (generally caused by environmental pressures) has given certain species characteristics making hem more fit for survival in their environment, example giraffes have long necks to reach leaves high in trees. Mutations start in a single animal of a single group, if this animal then successfully goes on to breed, there is a chance it may pass on the new genetic trait to its offspring thus increasing variation.

The species ability to reproduce sexually as opposed to A-sexually plays a significant factor as mutations in gamete can/will affect the next generation while somatic mutation will only affect that specific individual. 10. Evolution of large antlers on moose can be attributed to natural and sexual selection in several ways. Larger antlers and physical stature make the moose more desirable to females increasing chances of reproduction. Furthermore larger antlers and stature make the moose more formidable and allows him to better defend himself from attackers as well as commanding or leading a herd. 1. The desired genes of 1 species can be extracted and then inserted into others to attain the desired affect rather then waiting for natural mutation to occur as this takes many years and is random. 12)a) Pre-zygotic temporal isolation b) Pre-zygotic gametes isolation ) Pre-zygotic mechanical isolation d) Pre-zygotic habitat isolation e) Pre-zygotic behavioral isolation 13) The process starts when a geographic barrier is presented that splits a population forming 2 separate habitats and is a barrier to reproduction.

Once the separate populations become unable to interbreed this allows for new species to form. 14)a) Increased isolation could influence; physical characteristics such as height, allow for completely new species to form from lack of interbreeding, hybrids could form if the separated populations come into contact again after already forming new species. ) The moose population may separate, become geographically isolated, or even die off completely due to the changing environment.

Some habitats may become more favorable than others, territory and breeding grounds may divide or isolate, all the habitats become so inhospitable the moose population can’t survive. 15) Directional selection is present. Developing hollow bone structure makes a bird faster and lighter allowing them to fly longer, travel farther, and better evade predators. Those combined advantages lead to higher probability of reproduction and in turn lower mass becomes a dominant trait passed down to newer generations.