3. Luteinizing hormone (LH) triggers the release of testosterone by the follicle which causes the release of enzymes which rupture the ovary wall allowing the release of the secondary oocyte. After ovulation promotes the transformation of the follicle into the corpus luteum.
4. Follicle-stimulating hormone (FSH) – stimulate the formation of several primary follicles – only one of which will eventually develop while the other disintegrate. Also FSH stimulates the enzymes that lead to the formation of oestrogen.
15. The functions of the placenta Immune protection: protective molecules cover the surface of the early placenta “hiding” it from the maternal immune system so it is not rejected as ‘non-self’ due to the presence of the paternal genes.
16. The functions of the placenta Barrier: limits the transfer of blood components from the maternal to foetal system. Cells of the maternal immune system do not cross so reducing risk of immune rejection. (The placenta is not a barrier to heavy metals, nicotine, HIV, heroin or other toxins)
17. The functions of the placenta Immune protection: protective molecules cover the surface of the early placenta “hiding” it from the maternal immune system so it is not rejected as ‘non-self’ due to the presence of the paternal genes. Site of exchange of many solutes between maternal and foetal systems. Oxygen (aided by foetal haemoglobin), glucose, amino acids are all selective transported. CO 2 , urea and other waste materials diffuse the other way. Some antibodies pass from the mother during later pregnancy.
18. The functions of the placenta Barrier: limits the transfer of blood components from the maternal to foetal system. Cells of the maternal immune system do not cross so reducing risk of immune rejection. (The placenta is not a barrier to heavy metals, nicotine, HIV, heroin or other toxins) Endocrine function – the placenta takes over the production of oestrogen and progesterone as the corpus luteum degenerates ensuring the endometrium is maintained.
19. The functions of the placenta Barrier: limits the transfer of blood components from the maternal to foetal system. Cells of the maternal immune system do not cross so reducing risk of immune rejection. (The placenta is not a barrier to heavy metals, nicotine, HIV, heroin or other toxins) Endocrine function – the placenta takes over the production of oestrogen and progesterone as the corpus luteum degenerates ensuring the endometrium is maintained.
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