Question

Amnion and chorion consist of
A)Somatopleure
B)Splanchnopleure
C)Somatic mesoderm
D)Primary spermatocyte and spermatid

Answer 1

Hint: The layers enclosing the embryo within the uterus are extraembryonic membranes. Four layers are available: amnion, yolk sac, allantois, and chorion. In the amnion solution, the amnion is the innermost layer, enclosing the fetus, which protects it from mechanical tension.

Complete answer:
The bilateral folding of somatopleure, which is an extraembryonic organ, shapes both the amnion and the chorion in many animals. Somatopleure primarily consists of the lateral mesoderm of the ectoderm and the somatic plate.
The mixture of ectoderm and mesoderm or somatopleure contains the amnion, chorion and the lateral body wall of the embryo. The limbs are formed from somatic mesoderm cells caused by hox genes and the expression of other molecules for pain and epithelial-mesenchymal transition. Then the embryonic somatopleure is divided into three parts: the anterior limb bud growth, the posterior limb bud formation, and the non-limb wall formation. The bud-forming sections increase in size in the shape of mesenchyme at the somatic mesoderm, under the ectoderm.

The amnion is the internal membrane surrounding the foetus, while the embryo, the amnion, and other membranes are surrounded by the chorion. The amnion is packed with amniotic fluid that suspends the embryo, while the chorion also functions during the development of the embryo as a protective shield.

Hence, the correct answer is option (A)

Note: 1)Coelomic fluid surrounds the amniotic cavity for the first 12-13 weeks of gestation.
2)The amniotic membrane then fuses with the chorion, and the coelomic cavity is obliterated.