Fill in the blanks
(a) By the end of the ______  a _____ - of pregnancy, the fetus develops limbs and digits.
(b) By the end of _____  b ______ the body is covered with fine hair, eyelids separate and eyelashes are formed.
(c) After  ____  c ____ - of pregnancy, the embryos heart is formed.
 

In human beings, after one month of pregnancy, the embryo’s heart is formed. 

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

By the end of about 24 weeks (end of second trimester), the body is covered with fine hair, eye-lids separate, and eyelashes are formed.