Human Reproduction Test 9

Parturition is initiated by the fetus and the placenta. Leading to oxytocin signaling and uterine contractions. This reflex is called fetal ejection reflex.

• Oxytocin is the stimulant released from anterior pituitary to increase contractions of the uterine wall.
• Decreased levels of oxytocin can result in the inability to push the baby out.
• In such scenarios, the patient is injected with intravenous oxytocin to induce uterine contractions to deliver the baby.

• The colostrum is produced by the mammary glands for the first few days after the baby is born.
• The purpose is to protect the baby from the antigens it will be exposed after entering the world for the first time.

Hence it is enriched with antibodies.

Gestation is the period of time between conception and birth. It is calculated from the first day of the woman's last menstrual period. The gestation period of human beings is 270 days to 280 (approximately). It is usually about 36 weeks on average.

• Blood Flowing in mammalian umbilical cord is 100%  foetal (deoxygenated).
• Umbilical cord is an exception where arteries carry deoxygenated blood and veins carry the oxygenated blood (other exception is pulmonary vein and pulmonary artery).

• Between the amnion and embryo, there is an amniotic cavity filled with amniotic fluid secreted by both embryo and amnion. Amnion protects the embryo while amniotic fluid acts as a shock absorber and also prevents desiccation of the embryo.
• Functions of the Amnion: Amnion protects the embryo from shock and injury.

A hysterectomy is a surgery to remove a woman's uterus (also known as the womb). The uterus is where a baby grows when a woman is pregnant. During the surgery the whole uterus is usually removed. Your doctor may also remove your fallopian tubes and ovaries.

Parturition is the process of giving birth to a baby. Oxytocin is the hormone released by the posterior pituitary, it induces contraction in uterine muscles during parturition and induces labour. Estrogen, progesterone and prostaglandins also play an important role during parturition. Prolactin plays a significant role during lactation.

The development of the fetus from the time of fertilization in the womb of its mother is called the gestation period. In humans, the gestation period is for about 9 months or approximately 280 days. It is calculated from the incipience of their last menstrual period.

• Parturition is induced by a complex neuroendocrine mechanism as the signals for parturition originate from the fully developed foetus and the placenta produce foetal ejection reflex.
• This causes the release of oxytocin from the maternal pituitary which in turn causes stronger uterine contractions.

Parturition is induced by signals from both the fully developed foetus and the placenta. It induces mild uterine contractions called foetal ejection reflex.

• The mammary glands of the female undergo differentiation during pregnancy and start producing milk towards the end of pregnancy by the process called lactation.
• This process begins when the mammary gland is exposed to estrogen at puberty and is completed during the third trimester of pregnancy.

The milk produced during the initial few days of lactation is called colostrum which contains several antibodies absolutely essential to develop resistance for newborn babies.

At birth, when the oestrogen and progesterone levels fall due to loss of the placenta, prolactin is no longer inhibited and it stimulates the alveoli to secrete milk.

The antibodies in the colostrum help the body of the baby, which has been exposed to the external world full of different antigens, the ability to fight. This is called immunity.

• The major function of placenta is to provide the nutrition to the growing embryo and facilitates the removal of carbon dioxide and waste products by diffusion.
• The placenta also secretes estrogen however, not oxytocin.
• Oxytocin is a hormone secreted by posterior pituitary gland during parturition.

So, the correct option is 'Secrets oxytocin during parturition'.

Only c and d is correct

• The chorionic cells secrete a hormone named human chorionic gonadotrophin (hCG) which resembles and takes over the job of pituitary LH during pregnancy. The hCG maintains the corpus luteum and stimulates it to secrete progesterone.
• The progesterone maintains the endometrial lining and causes it to grow throughout pregnancy. This maintains menstruation.

So, the correct answer is 'hCG'.

Menstrual cycle occur in all primates and all mammals with few exception are viviparous.

• During the menstruation cycle, rapid secretion of LH induces rupture of Graafian follicle and thereby the release of an ovum (ovulation).
• The ovulation (ovulatory phase) is followed by the luteal phase during which the remaining parts of the Graafian follicle converts into the corpus luteum if fertilization occurs.
• The corpus luteum secretes large amounts of progesterone which maintains the events of pregnancy.
• During pregnancy, all events of the menstrual cycle stop and there is no menstruation and ovulation

So, the correct answer is 'Inhibits further ovulation'