Q. The fetal ejection reflex in humans triggers the release of _____
NTA AbhyasNTA Abhyas 2020
Solution:
Solution:
Vigorous contraction of the uterus at the end of pregnancy causes expulsion or delivery of the foetus. This process of delivery of the foetus resulting in childbirth is known as 'parturition'. It is induced by a complex neuroendocrine mechanism. The fully developed foetus originates the signals for parturition, in response to which mild uterine contractions called ''foetal ejection reflex' are induced by the placenta. Also called the 'Ferguson reflex', it shows a positive feedback mechanism and is initiated by the pressure created at the cervix or vaginal walls. It triggers the release of oxytocin from the maternal pituitary.
Oxytocin is produced in the hypothalamus and released by the posterior lobe of the pituitary which is present at the base of the brain. The mild contractions send signals to the hypothalamus, which activates the oxytocinergic neurons. This in turn activates the pituitary to release oxytocin in the blood which helps in increasing the uterine contractions. Further secretion of oxytocin is stimulated as the hormone induces the uterine muscle to cause stronger uterine contractions. The stimulatory reflex between the contractions and oxytocin secretion continues to result in stronger and stronger contractions. It is also released when people bond with each other and is also called 'love' or 'cuddle hormone'. It acts on breast and helps in lactation. It helps in its own release using a positive feedback control system. It also helps in prostaglandin production which in turn increases contractions.