It is called a sister chromatid, not a polar body.
I believe its D. response neuron.
Hope this helps!
Love, Grace-
The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
Answer:
Due to increment in food chains.
Explanation:
Biodiversity is actually the measure of changes in the ecosystem, genetic levels and various species levels. The sea otters introduced in California over last fifty years, increased the diversity in the ecosystem as well as in species too, thus changing the biodiversity. This was the impact of increase in food web in that particular area, the number of consumers, producers and prey increased thus increasing the biodiversity.
