Answer:
Habitat destruction and degradation, illegal shooting, and the contamination of its food source, largely as a consequence of DDT, decimated the eagle population.
1. A mudslide wipes out the side of a thriving hill: This is negative as many trees and other organisms will get destroyed.
2. A volcano erupts, covering the nearby land with lava: This is negative as molten and extremely hot lava can cause serious damage to its surroundings.
3. A forest is rapidly growing new plant life: This is positive because new plants are being grown.
4. Humans remove wolves from a national park to protect surrounding homes: This is positive for humans because humans will be safe but it is negative for the eco system as removal of wolves can upset the eco system cycle.
5. A dam is built in the middle of a river ecosystem to supply water to a nearby town: This is positive for humans as a new water resource is being developed for humans but negative for aquatic organisms as the dam can hamper their ecosystem and can cause pollution in water.
<span>Water covers around 70% of the Earth's surface and its high specific heat plays a very important role as it is able to absorb a lot of heat without a significant rise in the temperature. When temperatures decrease, the heat which is stored is released, restraining a rapid drop in temperature. The combined effect of these processes is a buffering of temperature on the Earth.</span>
I) Locus- the chromosomal site where a specific gene is located. A locus is a fixed position on a chromosome, like the position of a gene or a marker. Each chromosome carries ,many genes; human's estimated haploid (n) protein coding genes are about 20,000, on the 23 different chromosomes.
ii) Interference; the observed double crossover frequency differs from the expected double crossover frequency. Cross over interference is used to refer to the non-random placement of crossovers with respect to each other during meiosis. It results in widely spaced crossovers along chromosomes. Interference may exert its effect across whole chromosomes. As chromosomes in many eukaryotes are large, interference must be able to act over megabase lengths of DNA.
iii) Linkage- the tendency for genes located in close proximity on the same chromosome to be inherited together. Normally when two genes are close together on the same chromosome, they do not assort independently and are said to be linked. Whereas genes located on different chromosomes assort independently and have a recombination frequency of 50%, linked genes have a recombination frequency that is less than 50%.
iv) Recombination- the process by which a new pattern of alleles on a chromosome is generated. Genetic recombination is the production of offspring with combinations f traits that differ from those found in either parent. During meiosis in eukaryotes, genetic recombination involves the pairing of homologous chromosomes. This may be followed by information transfer between the chromosomes.
