Prepare for NEET Biology Human Reproduction (Parturition And Lactation) with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert guidance to understand labor contractions, birth, and milk production.
NEET Questions / Zoology / Human Reproduction / Parturition And Lactation
A pregnant woman experiencing Braxton Hicks contractions is given a tocolytic drug. Which of the following hormonal changes is MOST directly inhibited by this drug, thereby delaying parturition?
Increased progesterone
Decreased estrogen
Increased oxytocin
Decreased prostaglandins
During lactation, the milk ejection reflex is triggered by the suckling stimulus. Which neuroendocrine pathway is primarily responsible for this reflex?
Hypothalamus → Posterior pituitary → Oxytocin release
Hypothalamus → Anterior pituitary → Prolactin release
Anterior pituitary → Mammary glands → Progesterone secretion
Posterior pituitary → Adrenal cortex → Cortisol release
Colostrum, the first milk produced after parturition, differs significantly from mature milk. Which of the following is NOT a characteristic of colostrum compared to mature milk?
Higher fat content
Higher protein content
Rich in IgA antibodies
Contains laxatives
Which placental hormone inhibits prolactin secretion during pregnancy, preventing lactation before parturition?
Progesterone
hCG
Estrogen
hPL
A synthetic analog of oxytocin is administered to a postpartum woman experiencing difficulty with milk ejection. What is the primary target tissue of this drug in the mammary gland?
Myoepithelial cells
Lactocytes
Adipocytes
Fibroblasts
Which of the following correctly describes the feedback mechanism regulating prolactin secretion during lactation?
Suckling stimulates prolactin release, and high prolactin levels inhibit further prolactin release.
Suckling inhibits prolactin release, and low prolactin levels stimulate further prolactin release.
Prolactin release is independent of suckling and regulated solely by circadian rhythms.
High progesterone levels stimulate prolactin release during lactation.
Which hormone is primarily responsible for the milk ejection reflex (let-down reflex) during lactation?
Prolactin
Oxytocin
Estrogen
Progesterone
The expulsion of the placenta marks the end of which stage of parturition?
First stage
Second stage
Third stage
Fourth stage
Colostrum, the first milk produced after childbirth, is particularly rich in:
Fats
Carbohydrates
Antibodies
Iron
Which hormone inhibits uterine contractions during pregnancy and drops sharply before the onset of labor?
Estrogen
Progesterone
Oxytocin
Prolactin
