Pregnancy and Embryonic development Questions in English

(C) - Prolactin.
The placenta acts as an endocrine tissue and produces several hormones essential for maintaining pregnancy,including human chorionic gonadotropin $(hCG)$,human placental lactogen $(hPL)$,estrogens,and progestogens.
Prolactin is a hormone secreted by the anterior pituitary gland,not the placenta. Its primary function is to stimulate the mammary glands to produce milk.

(D) The correct answer is $D$.
In human development,the heart is formed after one month of pregnancy.
By the end of the second month of pregnancy,the foetus develops limbs and digits.
Therefore,the limbs and digits are developed after $8$ weeks.

(C) The correct answer is $C$.
During pregnancy,the placenta acts as an endocrine tissue and produces several hormones,including human chorionic gonadotropin $(hCG)$,human placental lactogen $(hPL)$,estrogens,and progestogens.
$hCG$,$hPL$,and relaxin are hormones that are produced in women only during pregnancy.
Additionally,the levels of other hormones such as estrogens,progestogens,cortisol,prolactin,and thyroxine are increased several-fold in the maternal blood to support fetal growth,metabolic changes,and the maintenance of pregnancy.

(A) The placenta acts as an endocrine tissue and produces several hormones essential for pregnancy,including $hCG$ (Human Chorionic Gonadotropin),$hPL$ (Human placental Lactogen),estrogen,and progesterone.
Relaxin is primarily secreted by the corpus luteum in the ovary,not by the placenta.

(B) The developmental stages of the human foetus are as follows:
$A$. The foetus movement starts and hair appears on the head occurs at $20$ weeks of pregnancy $(II)$.
$B$. The foetus develops limbs and digits by the end of $8$ weeks of pregnancy $(III)$.
$C$. The foetus develops external genital organs by $12$ weeks of pregnancy $(IV)$.
$D$. The foetus body is covered with fine hair,eyelids separate,and eyelashes are formed by $24$ weeks of pregnancy $(I)$.
Therefore,the correct matching is $A-II, B-III, C-IV, D-I$.