Final answer:
The fetal heart begins to beat at the end of the third week. All fetal organs are formed by the end of the eighth week of pregnancy. Fetal heart tones can be heard through ultrasound doppler around 10 to 12 weeks of pregnancy.
Step-by-step explanation:
The fetal heart begins to beat at the end of the third week of development.
All fetal organs are formed by the end of the eighth week of pregnancy.
Fetal heart tones can be heard through ultrasound doppler around 10 to 12 weeks of pregnancy.