What happens in the nanosecond before the sperm cell and egg cell fuse?

To your question, there are quite a few different views depending on religion or philosophy.

But scientifically, both sperm and egg are “alive”. The zygote that arises after the sperm cell has penetrated an egg cell is, of course, also “alive”. It consists of a single cell and does not yet resemble a human being, but it does have the ability to grow into a human being.

Regards,

Luke Bouwens