(a)[3]
Describe the role of progesterone during pregnancy.
(b(i))[2]
State the names of two useful substances that pass from the mother's blood into the fetus's blood.
(b(ii))[3]
Using the information in Fig. 5.1, suggest how the placenta is adapted to allow efficient diffusion.
(c)[3]
Fill in the Punnett square and work out the chance that the child will be Rh positive.