What happens during fertilization that makes the offspring unique compared to the original cells? Please write the answer in one sentence!
And please, if you do not know the answer, please don´t answer.

The union of an egg and sperm forming a zygote is known in biology as fertilization, during this process the zygote becomes a morula, meaning that the female reproductive cell divides after that union generating many other cells together into a solid ball of cells, giving rise to the embryo with the potential for development, fostered by chemical reactions among the sperm enzymes and the egg's plasma; mitosis and meiosis are included throughout the whole process.

Hydrogen gas is volatile.

Explanation: The limitation of the fuel cell for which the people are concerned is that hydrogen gas is volatile and the cars at high speed might crash.

This property of the fuel cell is a limitation because hydrogen is volatile at room temperature and can be made non volatile at lower temperatures which is not possible when it is used as a fuel.

So, it is a limitation of the fuel cells to be used in cars.