And in case you are wondering, the egg can live 24 -36 hours but if it is not fertilized in that amount of time, it is no longer viable.
Sperm, by contrast, can live 5-6 days in the woman's system (some research says longer, some says it's not very lively as late as 6 days).
Thus, say a couple has unprotected sex on January 1 only, and the woman ovulates on January 4. Conception would happen on January 4 or 5, even though they didn't have sex after the 1st.
Yes.
Ovulation = egg pops out of ovary and begins trip down Fallopian tubes.
Conception = moment sperm unites with egg
Implantation = embryo imbeds in uterine wall
(and 'fertilization' is the same as 'conception.')
Its When They Join Together Yes