Answer: Before about week 8 of pregnancy, a doctor may refer to the fetus as an embryo. The heart of an embryo starts to beat from around 5–6 weeks of pregnancy. Also, it may be possible to see the first visible sign of the embryo, known as the fetal pole, at this stage.
Serum or seminal fluid is that fluid........
Answer: the atrioventricular heart valve open and closed imcubent on different blood pressure on both sides.
Recycling is your answer.
Answer:
Development that takes place before the age of nine.
Primary sexual characteristics appear at birth and comprise both the external and internal genitalia (e.g., the penis and testes in men and the vagina and ovaries in women).
