When she ovulates. If she does not know her doctor can help her calculate it or she can pee on ovulation sticks from the pharmacy.
Because it is a mamal
Don't be silly
Because the sperm will die if it doesn't fertilise the egg. Survival at its basics.
the cockroach egg take about 19,20 or 21 days.
sperm
a sperm call job is to find an egg to fertilise
Yes they are. They are needed to fertilise the egg.
the sperm cells have to swim to the ovum and then fertilise it. and the egg cells have to reproduvce the offspring
You mean, how do they reproduce? They mate. And they don't lay eggs, they're livebearers.
an egg cell is the cell inside a womans ovary and is released once a month
an egg cell is the cell inside a womans ovary and is released once a month
on science books or here in the Internet