Explain/ describe how the placenta is adapted/ suited to its function.

Answer:

-Has numerous capillaries/highly vascularized; to increase concentration gradient for efficient exchange of materials;
-It has a thin membrane; for faster diffusion of materials/ reduce the distance travelled by substances;
-It has numerous (chorionic) villi; to increase the surface area of diffusion of substances;
-It has selective membrane; which allows selective diffusion of substances;
-It is glandular; to secrete hormones e.g. progesterone, oestrogen;
-Has counter current flow of maternal and foetal blood; to maintain steep concentrated gradient hence efficient diffusion of substances;

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