In Human beings, at the end of $12$ weeks (first trimester) of pregnancy, the following is observed
Movement of the foetus
Eyelids and eyelashes are formed
Most of the major organ systems are formed
The head is covered with fine hair
In which of the following the placenta forms an important structure in development
$A$ : If fertilization occurs, the corpus luteum is rescued from regression by human chorionic gonadotropin, which is produced by placenta.
$R$ : In first trimester the corpus luteum stimulates by $hCG$ is responsible for the production of progesterone.
By the and of the second month of pregnancy the foetus develops........
Placenta acts like a
Delete odd one (Only during pregnancy).