The normal duration of human embryonic development is about 280 days (40 weeks or 10 lunar months) and includes two main periods: germinal (first 8 weeks) and fetal (from the 9th to the 40th week).
Note: some scientists distinguish three periods of human embryonic development: initial (first week, before implantation), germinal (2nd – 8th weeks) and fetal (9th – 40th weeks).
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.