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Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Menstrual flow occurs due to lack of :

  1. Progesterone

  2. FSH

  3. Oxytocin

  4. Vasopressin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

the functions of the following hormones are:

Progesterone: Maintains the endometrium and pregnancy, its withdrawal results in menstrual flow or abortion respectively.
FSH: stimulates gonadal activity and hence is called gonadotropins. Its deficiency will cause non-maturation of germ cells.
Oxytocin: It stimulates vigorous contractions of the uterus at the time of childbirth and milk ejection from mammary glands.
Vasopressin: acts mainly at the kidney and stimulates resorption of water
and electrolytes by the distal tubules and thereby reduces the loss of water through urine (diuresis). Hence, it is also called an anti-diuretic hormone (ADH).
So, the correct answer is 'Option A- Progesterone'.

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Hormone controlling human menstrual cycle is

  1. Estrogen

  2. FSH

  3. LH

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

FSH is responsible for the growth of the Graafian follicle in the ovary. It also promotes the growth of follicles and promotes the secretion of oestrogen in the ovary.
Oestrogen is the female sex hormone. It is responsible for the endometrial thickening and it also helps in the healing of the wall of the uterus.
LH is the Leutenizing hormone and is responsible for the ovulation that takes place on the 14th day of the menstrual cycle.

So, the correct answer is 'All of the above'

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

What is the source of increase in concentration of estrogen in the proliferative phase of menstrual cycle?

  1. Hypothalamus

  2. Anterior pituitary

  3. Ovary

  4. Corpus lateum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • The follicular phase of the menstrual cycle is defined as the first day of menstruation until ovulation.
  • It is initiated by a rise in follicle-stimulating hormone levels on the first day of the cycle. Produced by the hypothalamus.
So, the correct option is 'Hypothalamus'.

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Low level of progesterone and estrogen in blood stimulate 

  1. FSH-RH production

  2. LH production

  3. GH production

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Low levels of progesterone and estrogen trigger the hypothalamus and anterior pituitary to release gonadotropins. This negative feedback loop stimulates the production of FSH and LH to initiate a new cycle.

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Secondary peak level of estrogen in menstruation cycle occurs due to ___________________.

  1. Formation of graafian follicle

  2. Ovulation

  3. Formation of primary follicle

  4. Formation of corpus luteum
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Secondary peak level of estrogen in menstruation cycle occurs due to formation of corpus luetum.


The menstrual cycle is controlled by a series of changes in hormone levels, primarily estrogen and progesterone. 

The menstrual cycle is divided into three stages:- follicular phase, ovulation, luteal phase.

The luteal phase begins with the formation of the corpus luetum stimulated by FSH and LH and ends in either progenny or luteolysis. The main hormone associated with this stage is progesterone which is produces by growing corpus luteum and is significantly higher during the luteal phase than any other phases of the cycle. 

Several days after ovulation, the increasing amount of estrogen produces by the corpus luetum may cause one or two days of fertile cervical mucus , lower basal body temperatures or both. It is known as secondary estrogen surge. The hormone produced by corpus luteum suppress production of the FSH and LH which leads to its atrophy. Death of corpus luteum results in falling levels of progesterone and estrogen which triggers the end of lateral phase and then the next cycle starts with the increase levels of FSH 

If Implantation occurs, the corpus luteum will continue producing progesterone for $8$ to $12$ weeks after which placenta takes over this function.

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

In the human female, menstruation can be deferred by the administration of?

  1. FSH only

  2. LH only

  3. Combination of FSH and LH

  4. Combination of estrogen and progesteron
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • When the production of progesterone and estrogen hormone stops in blood this leads to shed off the lying of uterine endometrium.
  • Progestrone and estradiol continue the hypertrophy of endo metrial lining in the uterus and fallopian tubes and maintain it throughout pregnancy.
  • Progesterone is also necessary for the proper implanation of the foetus in the uterine wall. It stimulates tyhe endometrial glands to secrete a nutrient fluid for the foetus, hence the term secretory phase.
  • Therefore, by supply of estrogen and progesterone the menstruation can be deferred
Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Which hormone induces the development of corpus luteum?

  1. LH

  2. Estrogen

  3. FSH

  4. LTH
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During menstruation cycle, maturation of the follicle is stimulated by follicle stimulating hormone (FSH) from the anterior pituitary, and oestrogen secreted by the follicle lining cells. 

Ovulation is triggered by a surge of luteinising hormone (LH) from the anterior pituitary, which occurs a few hours before ovulation. After ovulation, the follicle lining cells develop into the corpus luteum (yellow body), under the influence of LH from the anterior pituitary. The corpus luteum produces the hormone progesterone and some oestrogen. 
If the ovum is fertilised it embeds itself in the wall of the uterus, where it grows and develops and produces the hormone human chorionic gonadotrophin (hCG), which stimulates the corpus luteum to continue secreting progesterone and oestrogen for the first 3 months of the pregnancy, after which time this function is continued by the placenta. If the ovum is not fertilised the corpus luteum degenerates and a new cycle begins with menstruation. 
At the site of the degenerate corpus luteum an inactive mass of fibrous tissue forms, called as the corpus albicans. 

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Progesterone level falls leading to

  1. Gestation

  2. Menopause

  3. Lactation

  4. Menstruation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In human females the menstrual cycle starts with the menstrual phase, when menstrual flow occurs and it lasts for 3 - 5 days. The menstrual flow results due to breakdown of endometrial lining of the uterus and its blood vessels, which forms liquid that comes out through vagina. Menstruation only occurs if the released ovum is not fertilised and consequently, there is a fall in blood progesterone level. Post fertilization, the corpus luteum secretes large amounts of progesterone, which is essential for maintenance of the endometrium. 

Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

When the levels of progesterone fall in a human female, which event is expected to occur ? 

  1. The endometrial lining will thicken.

  2. The ovum will emerge from the ovary.

  3. The endometrial lining will slough off.

  4. The ovarian follicle will develop around the ovum.

  5. The levels of FSH and LH will peak.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
When the level of progesterone fall in human female, primary follicles grow in the ovary and outer two thirds of endometrium shed off.
So, the correct answer is 'The endometrial lining will slough off'.
Multiple choice biology coordination hormonal control of menstrual cycle regulation of the menstrual cycle life processes in living organisms- part 2

Which type of hormone controls the menstrual cycle in human being 

  1. LH

  2. FSH

  3. Progesterone

  4. FSH, LH, Estrogen
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The menstrual cycle is a complex process regulated by the interplay of several hormones. FSH, LH, and estrogen work together to manage follicle development, ovulation, and uterine lining changes.