Sexual Reproduction

Placenta also acts as an endocrine tissue and produces several hormones like human chorionic gonadotropin (hCG), human placental lactogen (hPL), estrogens, progestogens, etc.

Human chorionic gonadotropin (hCG) and human placental lactogen (hPL) are secreted by placenta and relaxin is also secreted by the ovary during later phase of pregnancy.

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

The baby's first stool is known as meconium.

5-7 days after fertilization, the blastocyst attaches to the wall of the uterus (endometrium). When it comes into contact with the endometrium it performs implantation.

At the end of the 8th week, the embryonic stage is over, and the fetal stage begins. By the end of the second month of pregnancy, the foetus develops limbs and digits.

Quantity of different antibodies found in human milk is in the order of IgA > IgG > IgM.

An example of monosomy is Turner Syndrome where the individual is born with only one sex chromosome, an X.

The most common natural cause of abortion of an embryo is chromosomal abnormality, which accounts for at least 50% of sampled early pregnancy losses.

The germ layers in organogenesis differ by three processes: folds, splits, and condensation.

Placenta connects to the fetus by an umbilical cord,  which contains two umbilical arteries and one umbilical vein.

In most marsupials, the allantois is avascular, having no blood vessels  but still serves the purpose of storing nitrogenous (NH₃) waste.

The eye begins to develop as a pair of optic vesicles on each side of the forebrain at the end of the 4th week of pregnancy.

Sesquizygotic twins: where two sperm fertilize  one ovum, forming a triploid, and then splitting.

Amnion is absent in amphibians and fish.

Yes, it is correct.

Human fertilization is the union of a human egg and sperm, usually occurring in the ampulla of the fallopian tube. The Fallopian tubes or oviducts are two tubes leading from the ovaries of female mammals into the uterus.