Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The average duration of human pregnancy is about months, which is called the gestation period.
Parturition is the process of delivery of the foetus (childbirth) and is induced by a complex neuroendocrine mechanism.
The signals for parturition originate from the fully developed foetus and the placenta which induce mild uterine contractions called the Foetal Ejection Reflex.
The Foetal Ejection Reflex triggers the release of the hormone Oxytocin from the maternal posterior pituitary.
Oxytocin acts on the uterine muscle () causing stronger uterine contractions, which in turn stimulates further secretion of oxytocin, creating a positive feedback loop.
Lactation is the production of milk by the mammary glands of the female towards the end of pregnancy.
Colostrum is the milk produced during the initial few days of lactation; it contains several antibodies (specifically ) essential to develop resistance/passive immunity for the newborn.
Breast-feeding during the initial period of infant growth is recommended by doctors for bringing up a healthy baby.
📐Formulae
💡Examples
Problem 1:
What triggers the release of oxytocin from the maternal pituitary during parturition, and what is the nature of its effect on uterine muscles?
Solution:
The trigger is the 'Foetal Ejection Reflex' initiated by the fully developed foetus and placenta. Its effect is a positive feedback loop leading to stronger uterine contractions.
Explanation:
Signals from the fully developed foetus cause mild contractions. These signals reach the hypothalamus, causing the posterior pituitary to release Oxytocin. Oxytocin causes the to contract more vigorously, which further stimulates oxytocin release until the baby is expelled.
Problem 2:
Identify the antibody found in colostrum and explain its significance for a newborn baby.
Solution:
The antibody is . It provides passive immunity to the infant.
Explanation:
Colostrum is the yellowish milk produced in the first few days after birth. It is rich in antibodies which help the infant fight off pathogens and develop a primary immune response, as the infant's own immune system is not yet fully functional.