Give biological explanations for the following:
The placenta is an important structure for the development of a foetus.
Topic: Importance of the placenta
Answer
The placenta is the link between mother and foetus. It TRANSPORTS oxygen, digested food, hormones and antibodies from the mother’s blood to the foetus, and REMOVES the foetal wastes — carbon dioxide, urea and uric acid — into the mother’s blood for disposal. It also SECRETES oestrogen and progesterone, which maintain the pregnancy, and acts as a BARRIER against many germs.
Give at least THREE roles, since the question asks why it is "important": EXCHANGE in both directions, HORMONE secretion, and PROTECTION.
THE POINT MOST OFTEN GOT WRONG: the blood of the mother and that of the foetus DO NOT MIX. They flow close together, separated by a thin membrane, and substances cross by diffusion. Writing that the mother’s blood flows into the baby is a definite error.
The placenta is remarkable because it does the work of several organs at once — LUNGS, DIGESTIVE SYSTEM, KIDNEYS and an ENDOCRINE GLAND — since none of the foetus’s own organs is yet functioning.