<span>In this item, we are to determine the location when we are in Shamu. Shamu is the name used to refer to several SeaWorld or killer whale which appeared in the shows at San Diego, California. Thus, the answer to this item is the first choice, San Diego, California. </span>
The answer is C. nitrogen.
Plants are main producers in ecosystems so, primary productivity of ecosystems depends on them. Carbon is necessary for plants, but it is widely present in plants. On the other hand, calcium and sodium are not as essential. However, nitrogen is important for plants because it is necessary to make proteins. Proteins take part in many different processes such as photosynthesis (this is actually primary productivity). But, nitrogen is not available to plants, they cannot absorb it simply from the air but rely on some symbiotic bacteria which are able to.
Allele frequency is a measure of the relative frequency of an allele on a genetic locus in a population.
Usually it is expressed as a proportion or a percentage.
In population genetics, allele frequencies show the genetic diversity of a species population or equivalently the richness of its gene pool.
The frequencies of all the alleles of a given gene often are graphed together as an allele frequency distribution histogram.
Population genetics studies the different "forces" that might lead to changes in the distribution and frequencies of alleles - in other words, to evolution.
Besides selection, these forces include genetic drift, mutation and migration.
1) they have similar chemical properties.
for example fluorine from the 17th column is a non metal so does all the elements of that group.
2)they have same valence electrons in their outermost shell
example
electronic configuration of
hydrogen 1, lithium 2,1, sodium 2,8,1 and so on.
3) have same valency.
