Question

In a human female's pregnancy.

By the end of 12 weeks ( $1^{\text{st}\text{~}}$ trimester), most of major organ systems are formed (not by end of 8 weeks).

After one month of pregnancy, the embryo's heart is formed.

By the end of second month of pregnancy, the foetus develops limbs and digits.

The first movements of foetus and appearance of hair on head are usually observed during the fifth month.