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Human Reproduction — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction4 Marks
Question
During the reproductive cycle of a human female, when, where and how does a placenta develop? What is the function of placenta during pregnancy and embryo development?
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Answer

After implantation, uterus, chorionic villi and uterine tissue become interdigitated (physically fused) to form a structural and functional unit between the developing embryo and the maternal body called placenta.
Functions:
  1. Placenta facilitates supply of oxygen and nutrients to the embryo.
  2. Removes carbon dioxide, waste material and excretory material produced by the embryo.
  3. Produces hCG/ hPL, estrogens and progestrogens.

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