The Placenta

• What is exchanged at the Placenta?

  Nutrients, oxygen, and waste products.
• What is the 1st role?

  Secretion of hormones; progesterone and oestrogen. It takes over from the Corpus Luteum.
• What is the 2nd role?

  Exchange of O2, CO2, nutrients and waste with the mother’s circulation.
• What is the 3rd role?

  Acts as a barrier to high blood pressure, blood born pathogens and toxins in the maternal blood.
• What is the 4th role?

  It allows maternal antibodies to protect the foetus by passive immunity.
• What is the 5th role?

  It provides protection from the mother’s immune system. Also prevents white blood cells from passing into the foetal blood.
• What is the structure of the Placenta?

  Large surface area, permeable, moist, concentration gradients, short diffusion pathway, countercurrent flow.