Tag: biology

Questions Related to biology

Pick up the correct information about menstrual cycle control.
1. Estrogen and progesterone of ovary

2. FSH of pituitary
3. FSH and LH of pituitary
4. Oxytocin.

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

  1. 1, 2, 3 correct

  2. 1, 2 correct

  3. 2, 4 correct

  4. 1, 3 correct

Show answer
Correct Option: D
Explanation:
Menstrual cycle starts with the menstrual flow followed by the follicle phase. During the follicular phase levels of gonadotropins (FSH and LH) increase and also the levels of estrogen increase. This rapid secretion of LH and FSH leads to LH surge and hence ovulation. After the ovulation luteal phase is accompanied by the formation of Corpus luteum. The Corpus luteum is responsible for the secretions of progesterone. 
So,  the correct option is '1, 3 correct'.

Disintegration of corpus luteum occurs due to inhibition of secretion of ............ hormone.

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

  1. LTH

  2. FSH

  3. Progesterone

  4. LH

Show answer
Correct Option: D
Explanation:

Corpus luteum is responsible for higher levels of progesterone whereas LH is responsible for its persistence. As soon as the level of LH decreases, degeneration of corpus luteum takes place. FSH does not play any significant role in the regression of corpus luteum whereas LTH does not have any role in the menstrual cycle.

So, the correct option is 'LH'.

GnRH secreted from hypothalamus mainly stimulates the release of

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

  1. Thyroxin from thyroid gland

  2. ADH from posterior pituitary

  3. FSH and LH from anterior pituitary

  4. Aldosterone from adrenals

Show answer
Correct Option: C
Explanation:

GnRH stimulates the synthesis and secretion of the two gonadotropins—luteinizing hormone (LH) and follicle-stimulating hormone (FSH)—by the anterior pituitary gland. In order to increase serum gonadotropin concentrations in patients with GnRH deficiency, the releasing hormone must be administered in pulses.
So the correct option is ' FSH and LH from anterior pituitary'.

Which of the following is not a function of progesterone?

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

  1. Gestation

  2. Inhibition of ovulation

  3. Uterine growth and development

  4. Stimulation of mammary secretion.

Show answer
Correct Option: D
Explanation:


Progesterone is the ovarian hormone which helps in the development of mammary glands but not the secretion of mammary glands.
So the correct option is 'Stimulation of mammary secretion.’

Estrogen is secreted by-

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

  1. Primary follicle

  2. Graafian follicle

  3. Corpus luteum

  4. Both (2) & (3)

Show answer
Correct Option: A
Explanation:

A primary follicle is surrounded by single or several layers of cuboidal, granulosa cells. It is an immature ovarian follicle. Based on the number of granulosa cell layers, the developing ovarian follicles can be categorised into three classes: primary follicles, secondary follicles, and early tertiary follicles.

So, the correct option is 'Primary follicle'.

FSH was administered to a group of rats who had their anterior glands removed.Compared with the control group of normal rats,which of the following events did NOT takes places in the experiment animals?

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

  1. Proliferation of the endometrium

  2. Maturation of a Graafian follicle

  3. Development of the corpos luteum

  4. Build - up of oestrogen in the blood stream

Show answer
Correct Option: A

Mainly which type of hormones control the menstrual cycle in human beings?

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

  1. FSH

  2. LH

  3. FSH, LH, estrogen

  4. Progesterone

Show answer
Correct Option: C

Which of the following events occur if fertilisation do not takes place. 

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

  1. Secretion of progesterone hormone increase

  2. Secretion of estrogen hormone stops

  3. Uterus inner wall layer and unfertilised egg will shed off

  4. Uterus inner wall increased and unfertilised egg will shed off

Show answer
Correct Option: C
Explanation:

If the egg is fertilised by a sperm as it travels down the Fallopian tube, then pregnancy occurs. 

But if the egg does not because fertilised, then the lining of the uterus (endometrium) is shed during ht mensuration.
Hence, the uterus inner wall and unfertilised egg will shed off if no fertilisation occurs.

During preovulatory phase?

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

  1. Concentration of estrogen remain low than progesteron

  2. LH is produced by follicular cells

  3. FSH stimulates the ovarian follicle to secrete estrogen

  4. FSH is positively regulated by estrogen

Show answer
Correct Option: C

A decrease in level of oestrogen and progesterone causes 

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

  1. Loss of endometrium

  2. Growth of dilation of endometrium

  3. Release of ova from ovaries

  4. Constriction of uterine blood vessels leading to sloughing of uterine epithelium

Show answer
Correct Option: D
Explanation:

    • Corpus luteum secretes large quantity of progesterone and small quantity of estrogen.
    • In the absence of fertilization, the corpus luteum degenerates resulting in decreased level of progesterone and estrogen.
    • This causes disintegration of the endometrium leading to menstruation, marking a new cycle.
    So, the correct option is 'Constriction of uterine blood vessels leading to sloughing of uterine epithelium'.