Download App

STD 12 - 2. human reproduction — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYSTD 12 - 2. human reproduction1 Mark
MCQ
Foetal ejection reflex in human female is induced by
  • A
    release of oxytocin from pituitary
  • ✓
    fully developed foetus and placenta
  • C
    differentiation of mammary glands
  • D
    pressure exerted by amniotic fluid.
✓

Answer

Correct option: B.
fully developed foetus and placenta
b
(b) : Parturition 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 foetal ejection reflex. This triggers release of oxytocin from the maternal pituitary. Oxytocin acts on the uterine muscle and causes stronger uterine contractions, which in turn stimulates further secretion of oxytocin. The stimulatory reflex between the uterine contraction and oxytocin secretion continues resulting in stronger and stronger contractions. This lead to expulsion of the baby out of the uterus through the birth canal.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q [1M]" from STD 12 - 2. human reproduction→STD 12 - 2. human reproduction — all question types→BIOLOGY STD 12 Science question papers→Bihar Board STD 12 Science question papers→Bihar Board question paper generator→

Similar questions

Flowers of insect pollinating plants are....
→
Test-tube baby is a technique where :
→
During isolation of DNA, addition of which of the following causes precipitation of purified DNA?
→
Genetic engineering helps to degrade .......... in the food:
→
Control of gene expression takes place at the level of:
→
Delete odd one
→
Rarely observed phenotype in population is called as:
→
Recombination of genes occurs at:
→
Pregnancy begins with implantation of
→
Following characters are most suitable for....

$(i)$ Due to alteration of $DNA$ sequences genotype is change.

$(ii)$ Changes occur in phenotype.

$(iii)$ Variation create in $DNA$

→