Two critical requirements must be met before light elements, like hydrogen or helium, will fuse and form heavier elements. the two requirements for nuclear fusion are

Explanation:

Nuclear fusion is the union of the protons and neutrons of two atoms to form a single atomic nucleus, of greater weight than those that gave rise to it.

In this process, an amount of energy equivalent to the difference between the binding energy of the new atom and the sum of the energies of the initial atoms is released.

For the fusion process to occur, it is necessary to overcome the electric repulsion force between the two nuclei, which grows in the direct ratio of the distance between them. This is only possible with extremely high temperatures, these reactions are also called thermonuclear reactions.

hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

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