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.
axesual thats how they reproduce
Waning gibbous
youre welcome
The right answer is D.
Intermolecular forces lead to the assembly of microscopic systems. They are responsible for the cohesion of matter in most macroscopic phases. These are weak forces compared to covalent bond strengths. They do not modify the nature of the molecular species and only influence their mode of assembly. The most well-known intermolecular bonds are the Van der Waals bond and the hydrogen bond.
The greater the intermolecular forces, the more the aspect of the element will tend to be more condensed (gas <liquid <solid).