What is the organ of pregnancy where nutrients are exchanged between mother and baby?

• A. Uterus
• B. Placenta
• C. Amnion
• D. Zygote

Answer: (B)

Nutrients and other substances pass between mother and baby through the placenta, which serves as the interface between maternal and fetal circulation. The placenta allows the transfer of nutrients, oxygen, and waste products across its membranes while keeping maternal and fetal blood mostly separate. Nutrients such as glucose, amino acids, and fatty acids move from the mother’s blood into the fetal circulation via placental villi through diffusion and active transport. The placenta also functions as an endocrine organ, producing hormones to support pregnancy.

The uterus is the muscular environment that houses the developing fetus, not the site of direct nutrient exchange. The amnion is a protective membrane around the fetus filled with amniotic fluid, and the zygote is the fertilized egg that becomes the embryo.