Question

how do human embryonic heart begins beating ?

Answer 1

the following answer is in detail.kindly make small sentences out of this to get a briefed answer.
It's technically not a fully formed human "heart" that starts beating at around 4-6 weeks. It's a mass of tiny cells (that will someday form a human heart) that start to spontaneously contract, one cell contraction initiating the cell next to it to contract alongside and the next, like a chain reaction.. The rhythm of these contracts is not regulated yet by any nervous system like the brain (which also isn't formed yet).

These cells contract because of a specific sequence of DNA in each of those cells that is activated which tell those particular cells to become "heart cells." Hence, these proto-heart cells contract instead of remaining still and they don't form into liver cells or eye ball cells or skin cells.

Or maybe you could just take a human development course in college, or pick up a BOOK on human development. You know, like the rest of us do when we want to know something about the world -- instead of asking an atheist to explain things to you and thus robbing yourself of the opportunity to challenge yourself intellectually and maybe-for-once use those critical thinking skills you so dearly need to exercise.

Thanks so much

Answer 2

The human embryonic heart begins beating approximately 21 days after fertilization, or five weeks after the last normal menstrual period (LMP), which is the date normally used to date pregnancy in the medical community. ... Conductive cells develop the bundle of His and carry the depolarization into the lower heart.