1. The estrous cycle is a characteristic of
(a) human males only
(b) human females only
(c) mammalian males other than primates
(d) mammalian females other than primates
2. Test tube baby is one who
(a) is born out of artificial insemination
(b) has undergone development in a test tube
(c) is born out of the technique of fertilization in vitro
(d) has been developed without fertilization
3. Amniocentesis is a technique
(a) by which the essential amino acids in the body can be estimated
(b) by which any chromosomal anomalies in the foetus can be detected
(c) in which the sex of the foetus can be reversed
(d) that can be used for correcting genetic disorders of the foetus
4. After ovulation the collapsed ovarian follicle shrinks and becomes filled with cell to form
(a) corpus luteum
(b) corpus albicans
(c) corpus atresia
(d) corpus adiposum
5. The growth of corpus luteum is initiated by
(a) Human chorionic gonadotropin
(b) Follicle stimulating hormone
(c) Luteinizing hormone
(d) Prolactin
6. Exponential growth of cells is a characteristic feature of
(a) tissue culture cells
(b) multicellular organisms
(c) unicellular organisms
(d) embryo
7. Cleavage in mammalian egg is
(a) superficial meroblastic
(b) discoidal meroblastic
(c) unequal holoblastic
(d) equal holoblastic
8. During embryonic development, the establishment of polarity along anterior/ posterior, dorsal/ventral or medial/lateral axis is called
(a) pattern formation
(b) organizer phenomena
(c) axis formation
(d) anamorphosis
9. If mammalian ovum fails to get fertilized, which one of the following is unlikely?
(a) Corpus luteum will disintegrate
(b) Progesterone secretion rapidly declines
(c) Estrogen secretion further decreases
(d) Primary follicle starts developing
10. Grey crescent is the area
(a) at the point of entry of sperm into ovum
(b) just opposite to the site of entry of sperm into ovum
(c) at the animal pole
(d) at the vegetal pole
11. Withdrawal of which of the following hormones is the immediate cause of menstruation?
(a) FSH
(b) FSH-RH
(c) Progesterone
(d) Estrogen
12. In the human female, menstruation can be deferred by the administration of
(a) combination of FSH and LH
(b) combination of estrogen and progesterone
(c) FSH only
(d) LH only
13. In humans, at the end of the first meiotic division, the male germ cells differentiate into the
(a) primary spermatocytes
(b) secondary spermatocytes
(c) spermatids
(d) spermatozonia
14. Which extra-embryonic membrane in humans prevents desiccation of the embryo inside the uterus?
(a) Chorion
(b) Allantois
(c) Yolk sac
(d) Amnion
15. Which one of the following statements is incorrect about menstruation?
(a) During normal menstruation about 40 ml blood is lost
(b) The menstrual fluid can easily clot
(c) At menopause in the female, there is especially abrupt increase in gonadotropic hormones
(d) The beginning of the cycle of menstruation is called menarche
16. Which one of the following is the correct matching of the events occurring during menstrual cycle?
(a) Proliferative phase: Rapid regeneration of myometrium and maturation of Graffian follicle.
(b) Development of corpus luteum: Secretory phase and increased secretion of progesterone.
(c) Menstruation: Break down ofmyometrium and ovum not fertilised.
(d) Ovulation: LH and FSH attain peak level
And sharp fall in the secretion of progesterone.
17. Seminal plasma in humans is rich in
(a) fructose and calcium but has no enzymes
(b) glucose and certain enzymes but has no calcium ‗
(c) fructose and certain enzymes but poor in calcium
(d) fructose, calcium and certain enzymes
18. Foetal ejection reflex in human female is induced by
(a) release oxytocin from pituitary
(b) fully developed foetus and placenta
(c) differentiation of mammary glands
(d) pressure exerted by amniotic fluid
19. Foetal ejection reflex in human female is induced by
(a) release oxytocin from pituitary
(b) fully developed foetus and placenta
(c) differentiation of mammary glands
(d) pressure exerted by amniotic fluid
20. The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testes is:
(a) spermatogonia – spermatocyte – spermatid – sperms
(b) spermatid – spermatocyte – spermatogonia – sperms
(c) spermatogonia – spermatid – spermatocyte – sperms
(d) spermatocyte – spermatogonia – spermatid – sperms
21. Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female?
(a) maintenance of the hypertrophical endometrial lining
(b) maintenance of high concentration of sex hormones in the blood stream
(c) retention of well -developed corpus luteum
(d) fertilisation of the ovum
22. A change in the amount of yolk and its distribution in the egg will affect
(a) pattern of cleavage
(b) number of blastomeres produced
(c) fertilization
(d) formation of zygote
23. In vitro fertilisation is a technique that involves transfer of which one of the following into the fallopian tube?
(a) Embryo only, upto 8 cell stage
(b) Either zygote or early embryo upto 8 cell stage
(c) Embryo of 32 cell stage
(d) Zygote only
24. Sertoli cells are found in
(a) ovaries and secrete progesterone
(b) adrenal cortex and secrete adrenaline
(c) seminiferous tubules and provide nutrition to germ cells
(d) pancreas and secrete cholecystokinin
25. Vasa efferentia are the ductules leading from
(a) testicular lobules to rete testis
(b) rete testis to vas deferens
(c) vas deferens to epididymis
(d) epididymis to urethra
26. Seminal plasma in human males is rich in:
(a) fructose and calcium
(b) glucose and calcium
(c) DNA and testosterone
(d) ribose and potassium
27. The permissible use of the technique amniocentesis is for
(a) detecting sex of the unborn foetus
(b) artificial insemination
(c) transfer of embryo into the uterus of the surrogate mother
(d) detecting any genetic abnormality
28. The signals for parturition originate from
(a) placenta only
(b) placenta as well as fully developed foetus
(c) oxytocin released from maternal pituitary
(d) fully developed foetus only
29. The first movements of the foetus and appearance of hair on its head are usually observed during which month of pregnancy?
(a) Fourth month
(b) Fifth month
(c) Sixth month
(d) Third month
30. The second maturation division of the mammalian ovum occurs
(a) shortly after ovulation before the ovum makes entry into the fallopian tube
(b) until after the ovum has been penetrated by a sperm
(c) until the nucleus of the sperm has fused with that of the ovum
(d) in the graafian follicle following the first maturation division
31. Which one of the following statements about human sperms is correct ?
(a) Acrosome has a conical pointed structure and piercing and penetrating the egg, resulting in fertilisation
(b) The sperm lysins in the acrosome dissolve dissolve the egg envelope facilitating fertilisation
(c) Acrosome serves as a sensory structure leading the sperm towards the ovum
(d) Acrosome serves no particular function
32. Which one of the following statements about morula in humans is correct?
(a) It has almost equal quantity of cytoplasm as an uncleaved zygote but much more DNA
(b) It has far less cytoplasm as well as less DNA than in an uncleaved zygote
(c) It has more or less equal quantity of cytoplasm and DNA as in uncleaved zygote
(d) It has more cytoplasm and more DNA than an uncleaved zygote
33. The part of fallopian tube closest to the ovary is
(a) isthmus
(b) infundibulum
(c) cervix
(d) ampulla
34. If for some reason, the vasa efferentia in the human reproductive system gets blocked, the gametes will not be transported from
(a) testes to epididymis
(b) epididymis to vas deferens
(c) ovary to uterus
(d) vagina to uterus
35. The testes in humans are situated outside the abdominal cavity insides pouch called scrotum. The purpose served is for
(a) maintaining the scrotal temperature lower than the internal body temperature
(b) escaping any possible compression by the visceral organs
(c) providing more space for the growth of epididymis
(d) providing a secondary sexual feature for exhibiting the male sex
36. Signals for parturition originate from:
(a) Both placenta as well as fully developed foetus
(b) Oxytocin released from maternal pituitary
(c) Placenta only
(d) Fully developed foetus only
37. What happens during fertilisation in humans after many sperms reach close to the ovum?
(a) Secretions of acrosome helps one sperm enter cytoplasm of ovum through zona pellucida
(b) All sperms except the one nearest to the ovum lose their tails
(c) Cells of corona radiata trap all the sperms except one
(d) Only two sperms nearest the ovum penetrate zona pellucida
38. About which day in a normal human menstrual cycle does rapid secretion of LH (Popularly called LH-surge) normally occurs?
(a) 14th day
(b) 20th day
(c) 5th day
(d) 11th day
39. Which one of the following statements is false in respect of viability of mammalian sperm?
(a) Sperm is viable for only up to 24 hours.
(b) Survival of sperm depends on the pH of the medium and is more active in alkaline medium.
(c) Viability of sperm is determined by its motility.
(d) Sperms must be concentrated in a thick suspension.
40. Signals for parturition originate from:
(a) Both placenta as well as fully developed foetus
(b) Oxytocin released from maternal pituitary
(c) Placenta only
(d) Fully developed foetus only
41. In a normal pregnant woman, the amount of total gonadotropin activity was assessed. The result expected was
(a) High level of circulating FSH and LH in the uterus to stimulate implantation of the embyro
(b) High level of circulatting HCG to stimulate endometrial thickening
(c) High level of FSH and LH in uterus to stimulate endometrical thickening
(d) High level of circulating HCG to stimulate estrogen and progesterone synthesis.
42. The Leydig cells found in the human body are the secretory source of
(a) Progesterone
(b) intestinal mucus
(c) glucagon
(d) androgens
43. The foetal ejection reflex in humans triggers release of
(a) Oxytocin from maternal pituitary
(b) Oxytocin from foetal pituitary
(c) Human Chorionic Gonadotropin (hCG) from placenta
(d) Human Placental Lactogen (hPL) from placenta
44. The secretory phase in the human menstrual cycle is also called
(a) luteal phase and lasts for about 6 days
(b) follicular phase lasting for about 6 days
(c) luteal phase and lasts for about 13 days
(d) follicular phase and lasts for about 13 days
45. Menstrual flow occurs due to lack of:
(a) FSH
(b) Oxytocin
(c) Vasopressin
(d) Progesterone
46. What is the correct sequence of sperm formation?
(a) Spermatogonia, spermatocyte, spermatozoa, spermatid
(b) Spermatogonia; spermatozoa, spermatocyte, spermatid
(c) Spermatogonia, spermatocyte, spermatid, spermatozoa
(d) spermatid ,spermatocycte, spermatogonia , spermatozoa
47. Which one of the following is not the function of placenta? It:
(a) secretes estrogen
(b) facilitates removal of carbon dioxide and waste material from embryo.
(c) secretes oxytocin during parturition
(d) facilitates supply of oxygen and nutrients to embyo
48. which of the following best illustrates FEEDBACK in development?
(a) As tissue (X) develops , it seceatessomething that slows down the growth of tissue (Y)
(b) Tissue (X) secretes RNA which changes the development of tissue (Y)
(c) As tissue (X) develops it secretes enzymes that inhibit the development of tissue (Y)
(d) As tissue (X), develops it secretes something that induces tissue (Y) to develop
49.signals for parturition origionate from
(a) Both placenta as well as fully developed fopetus
(b) Oxytocin released from maternal pituitary
(c) Placenta only
(d) Fully developed foetus only
50. Select the option which correctly matches the endocrine gland with its hormone and its function Endocrine gland — Hormone — Function
(a) Ovary — FSH — stimulates follicular development and the secretion of estrogens.
(b) Placenta – estrogen — initiates secretion of the milk.
(c) Corpus – estrogen — essential for luteum maintenance of endometerium
(d) Leydig – androgen — initiates the cells production of sperms.
51. The foetal ejection reflex in humans triggers release of
(a) Oxytocin from maternal pituitary
(b) Oxytocin from foetal pituitary
(c) Human Chorionic Gonadotropin (hCG) from placenta
(d) Human Placental Lactogen (hPL) from placenta
52.Which one of the following statements with regard to embryonic development in humans is correct?
(a) In the second cleavage division, one of the two blastomeres usually divides a little sooner than the second.
(b) Cleavage divisions bring about considerable increase in the mass of protoplasm.
(c) With more cleavage divisions, the resultant blastomeres become larger and larger.
(d) Cleavage division results in a hollow ball of cells called morula.
53. Through which of the following vas deference runs upward from epididmis and enter the abdominal cavity ?
(a) Ejaculatory duct
(b) Inguinal canal
(c) Urethra
(d) (a)and(b)
54. Capacitation occurs in
(a) female reproductive tract
(b) rete testis
(c) epididymis
(d) vas deferens
55. In male accessory reproductive glands which is incorrect ?
(a) Seminal vesicle
(b) Prostate gland
(c) Urinary bladder
(d) Bulbourethral gland
56. Several hormones like hCG, hPL, estrogen, progesterone are produced by
(a) placenta
(b) Fallopian tube
(c) ovary
(d) pituitary.
57. Which one of the following events is correctly matched with the time period in a normal menstrual cycle?
(a) Release of egg : 5th day
(b) Endometrium regenerates : 5-10 days
(c) Endometrium secretes nutrients for implantation : 11-18 days
(d) Rise in progesterone level : 1-15 days
58. Select the incorrect statement.
(a) LH triggers secretion of androgens from the Leydig cells.
(b) LH and FSH decrease gradually during the follicular phase.
(c) FSH stimulates the sertoli cells which help in spermiogenesis.
(d) LH triggers ovulation in ovary.
59. In human females, meiosisII is not completed until
(a) puberty
(b) uterine implantation
(c) birth
(d) fertilization
60. What is provided to sperm by secretion of prostate gland ?
(a) Nourishes
(b) Activating
(c) Lubricant
(d) (a)and (c) both
61. Which of the following events is not
associated with ovulation in human female?
(a) Full development of Graafian follicle
(b) Release of secondary oocyte
(c) LH surge
(d) Decrease in estradiol
62. Corpus luteum is a mass of cells found in
(a) brain
(b) pancreas
(c) ovary
(d) spleen
63. Which of the following cells during gametogenesis is normally diploid ?
(a) Secondary polar body
(b) Primary polar body
(c) Spermatid
(d) Spermatogonia
64. What is the function of bulbourethral gland secretion ?
(a) Nourishes sperms
(b) role in activating sperms
(c) Serves as a lubricant during sexual intercourse
(d) Enhancing the motility of sperms
65. Hysterectomy is surgical removal of
(a) vas deferens
(b) mammary glands
(c) uterus
(d) prostate gland
66. Ejaculation of human male contains about 200 – 300 million sperms, of which for normal fertility ____ % sperms must have normal shape and size and at least ____% must show energetic motility.
(a) 40, 60
(b) 60, 40
(c) 50, 50
(d) 30, 70
67. The main function of mammalian corpus luteum is to produce
(a) human chorionic gonadotropin
(b) relaxin only
(c) estrogen only
(d) progesterone
68. What is the function of bulbourethral gland secretion ?
(a) Nourishes sperms
(b) role in activating sperms
(c) Serves as a lubricant during sexual intercourse
(d) Enhancing the motility of sperms
69. Ectopic pregnancies are referred to as
(a) pregnancies terminated due to hormonal imbalance
(b) implantation of defective embryo in the uterus
(c) pregnancies with genetic abnormality
(d) implantation of embryo at site other than Uterus
70. Internally the penis is…………
(a) Composed of three cylindrical mass of conective tissue bound together
(b) Composed of three cylindrical mass of tissue bound together by firus tissue
(c) Composed of three cylindrical mass of epithelium tissue bound together
(d) Composed of three mass of tissue only
71. Hysterectomy is surgical removal of
(a) mammary glands
(b) vas deferens
(c) uterus
(d) prostate gland
72. Capacitation occurs in :
(a) Epididymis
(b) Vas deferens
(c) Female reproductive tract
(d) Rete testis
73. The difference between spermiogenesis and spermiation is
(a) In spermiogenesis spermatids are formed, while in spermiation spermatozoa are formed.
(b) In spermiogenesis spermatozoa are formed, while in spermiation spermatids are formed.
(c) In spermiogenesis spermatozoa are formed, while in spermiation spermatozoa are released from sertoli cells into the cavity of seminiferous tubules.
(d) In spermiogenesis spermatozoa from sertoli cells are released into the cavity of seminiferous tubules, while in spermiation spermatozoa are formed.
74. The amnion of mammalian embryo is derived from
(a) ectoderm and mesoderm
(b) endoderm and mesoderm
(c) ectoderm and endoderm
(d) mesoderm and trophoblast
75. Hormones secreted by the placenta to maintain pregnancy are
(a) hCG, hPL, progestogens, prolactin
(b) hCG, hPL, estrogens, relaxin, oxytocin
(c) hCG, progestogens, estrogens, glucocorticoids
(d) hCG, hPL, progestogens, estrogens
76. Match the items given in Column I with those in Column II and select the correct option given below :
Column I Column II
a. Proliferative Phase i. Breakdown of endometrial lining
b. Secretory Phase ii. Follicular Phase
c. Menstruation iii. Luteal Phase
a b c
(a) iii ii i
(b) i iii ii
(c) iii i ii
(d) ii iii i
77. Extrusion of second polar body from egg nucleus occurs :
(a) after entry of sperm but before fertilization
(b) after fertilization
(c) before entry of sperm into ovum
(d) simultaneously with first cleavage
78. Meiotic division of the secondary oocyte is completed
(a) After zygote formation
(b) At the time of fusion of a sperm with an ovum
(c) Prior to ovulation
(d) At the time of copulation
79. Match the following columns and select the correct option.
Column-I Column-II
(a) Placenta (i) Androgens
(b) Zona pellucida (ii) Human Chorionic Gonadotropin (hCG)
(c) Bulbo-urethral (iii) Layer of the ovum glands
(d) Leydig cells (iv) Lubrication of the Penis
(a) (b) (c) (d)
(1) (iii) (ii) (iv) (i)
(2) (ii) (iii) (iv) (i)
(3) (iv) (iii) (i) (ii)
(4) (i) (iv) (ii) (iii)
80. Receptors for sperm binding in mammals are present on :
(a) Zona pellucida
(b) Corona radiata
(c) Vitelline membrane
(d) Perivitelline space
81. Which of these is not an important component of initiation of parturition in humans ?
(a) Release of Prolactin
(b) Increase in estrogen and progesterone ratio
(c) Synthesis of prostaglandins
(d) Release of Oxytocin
82. Which of the following secretes the hormone, relaxin, during the later phase of pregnancy?
(a) Uterus
(b) Graafian follicle
(c) Corpus luteum
(d) Foetus
Solutions :
1.Solution: (d) Estrous cycle is the characteristic of mammalian females other than primates. It is due to estrogen hormone. Estrous is the
period during which ovulation occurs and the females mate with male.
2.Solution: (c) In test tube baby, fertilization of the sperm and the ova is carried out in lab conditions (in vitro) and when the embryos have
reached the 32-celled stage, it is implanted back into the uterus of the mother.
3.Solution: (b) Amniocentesis is the most widely used method for prenatal detection of many genetic disorders. It is also a technique used for determining the sex of the foetus.
4.Solution: (a) After ovulation ovarian follicle, undergo several stages of degeneration the pilicular cells inlarge and fill with a yellow fluid to
form corpus luteum.
5.Solution: (c) Luteinizing hormone causes ovulation. The remaining cells of ovarian follicle are stimulated by LH to develop corpus luteum.
6.Solution: (d) Embryo growth graph is ‘J’ shaped.
7.Solution: (c) Cleavage in the human zygote is holoblastic i.e. it divides the zygote and the blastomeres completely into daughter cells.
But it is unequal as the blastomeres differ in size.
8.(a) pattern formation
(b) organizer phenomena
(c) axis formation
(d) anamorphosis
9.Solution: (c) Since corpus luteum degenerates so progesterone also decreases rapidly (progesterone is essential for maintenance of pregnancy). Also estrogen continues to curve growth of the endometrium which ultimately becomes thick enough to break down and cause menstruation. Hence choice (c) is incorrect as estrogen secretion does not decreases further. Primary follicles start developing.
10.Solution: (b) On the surface of the egg opposite to the point of sperm entry, the peripheral area of the egg becomes lighter in colour and
assumes a grey appearance. This area is crescentric in shape and is known as the grey crescent.
11.Solution: (c) Progesterone hormone which is secreted by the corpus luteum in the ovaries is responsible to stop ovulation (during pregnancy) and fixes the foetus to the uterine wall, facilitates placenta formation and controls the foetus development in uterus. If this hormone is withdrawn then fixation of foetus to uterine wall will not take place, formation of placenta will also not take place, ovulation starts from the ovaries and hence in human female menstruation starts.
12. Solution: (b) The progesterone 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 implantation of the foetus in the uterine wall. It stimulates the endometrial
glands to secrete a nutrient fluid for the foetus, hence the term secetory phase. The progesterone inhibits the release of FSH so that it may not develop additional follicles and eggs.
13. Solution: (b)In human, at the end of the first meiotic division, the male germ cells differentrate into the secondary.
14.Solution: (d)Amnion is an extraembryonic membrane in human prevents desiccation of the embryo inside the uterus. Amnion is a membrane that encloses the embryo of reptiles, birds and mammals within the amniotic cavity. This cavity is filled with amniotic fluid, in which the embryo is
protected from dessication and from external pressure.
15.Solution: (b) In human female, the periodic discharge of blood, mucus and cellular debris from uterine wall from non-pregnant women of
sexual maturity is known as menstrual cycle. Few hours before the start of mensuration, the spiral arterioles constrict ne by one resulting into the blanch mucosa. The mucosa shrinks and the death of the blood deprived tissues takes place.
16.Solution : (b) The corpus luteum is essential for establishing and maintaining pregnancy in females. In the ovary, the corpus luteum secretes estrogens and progesterone, which are steroid hormones responsible for the thickening of the endometrium and its development and maintenance, respectively.
17.Solution: (c) Human seminal plasma is a complex mixture of proteins, glycoproteins, pepti des, glycopepties, and prostaglandins secreted by organs of the male reproductive tract. The components of this fluid have been implicated in the suppression of immune response, agonistic effects on sperm-egg binding, and promotion of successful implantation of the human embryo. Seminal plasma in humans is rich in fructose and certain enzymes but poor in calcium.
18.Solution: (b) Foetal ejection reflex in human female is induced by fully developed foetus and placenta. When a woman is in a lithotomy or semi-sitting position, the Foetal Ejection Reflex is impaired and the increased pain caused by the sacrum‘s inability to move as the baby descends can be intolerable.
19.Solution: (b) Foetal ejection reflex in human female is induced by fully developed foetus and placenta. When a woman is in a lithotomy or semi-sitting position, the Foetal Ejection Reflex is impaired and the increased pain caused by the sacrum‘s inability to move as the baby descends can be intolerable.
20.Solution: (a) The formation of sperms in mature human testes completed in three important phases in gametogenesis- multiplication, growth
and maturation phase. During these phases primarily germ cells change into spermatogonia then spermatocyte during growth phase which change into spermatoids and spermatids into sperms.
21.Solution: (d) Fertilization of ovum is the most likely root cause why menstruation is not taking place in regularly cycling human female. In order
for fertilization to occur, one of these sperm must attach itself to the ovum and penetrate its outer surface. The fertilized ovum will then continue travelling down the fallopian tube, taking several days until it reaches the uterus. When it arrives, it attaches itself to the lining of the uterus
and continues to grow. If the ovum is not fertilized it will die and the progesterone and oestrogen hormone levels will drop. Without these hormones the prepared uterus lining breaks up and is released through the vagina. This is known as a ‗period‘.
22. Solution: (a) A change in the amount of yolk and its distribution in the egg will affect pattern of cleavage. The pattern of cleavage is
influenced by the amount of yolk in the egg. In eggs with less yolk, cleavages are equal, and the resulting blastomeres are of similar size. If the yolk is localized, such as in frog eggs, then clevages are unequal, the cells derived from the yolky region (the vegetal pole) are larger than those derived from the region without yolk (the animal pole).
23. Solution: (a) In vitro fertilization is a process where fertilization of egg occurs outside the mother‘s womb. This method is used as a major treatment for infertility. This method involves the removal of eggs from the female ovaries. This egg is then allowed to fertilize with sperm in a fluid medium in a test tube. The zygote is allowed to develop for a week. Either zygote or early embryo up to 8 blastomeres is then transferred into
the fallopian tube to complete its further development. If the embryo is with more than 8 blastomeres, it is transferred into uterus for successful pregnancy. A baby conceived by fertilization that occu rs outside mother body is called test tube baby.
24.Solution: (c) Sertoli cells are found in the walls of seminiferous tubules of the testes. They anchor and provide nutrition to the developing germ cells especially the spermatids.
25. Solution: (b) Vasa efferentia are ductules leading from rete testis to vas deferens. The rete testis is an anastomosing network of tubules
located in the hilum of the testicles that carries sperm from the seminiferous tubules to the vasa efferentia.
26. Solution: (a) Seminal plasma in human males are rich in fructose, calcium and certain enzymes. They provide a medium for transport of
sperms, nourishes and activates sperms.
27.Solution: (d) Amniocentesis involves prenatal diagnosis of metabolic error and other genetic abnormalities.
28. Solution: (b) Parturition is the process of delivery of the foetus. The signals for parturition originate from the fully developed foetus and
placenta that induce uterine contraction called foetal ejection reflex. This triggers the release of oxytocin hormone from pituitary. This in turn leads to expulsion of the baby out of uterus.
29. Solution: (b) In human beings, after one month of pregnancy, the embryo‘s heart is formed. By end of second month pregnancy, the foetus develops limbs and digits. By end of 12 weeks, major organ systems are formed. After fifth month, the first movement off foetus and appearance of hair on its head are observed. By the end of 24 weeks, the body is covered with hairs, eye lids separate and eyelashes are formed.
30. Solution: (b) In Oogenesis, the second maturation division occurs until after the ovum has been penetrated by a sperm. Oogenesis involves the formation of haploid female gametes, ova, from this diploid egg mother cells, oogonia of ovary of female organism.
31. Solution: (b) Acrosome a small pointed structure at the tip of nucleus. It breaks down just before fertilization, releasing hydrolytic enzymes
that assist penetration between follicle cells that surrounds the ovum, thus facilitating fertilization.
32.Solution: (a) Morula is a solid ball contained within the zone pellucida. It has almost equal quantity of cytoplasm as an uncleaved zygote but
much more DNA. Human Reproduction 249
33.Solution: (b) The part of fallopian tube closest to the ovary is infundibulum. Infundibulum possess finger-like projections called fimbriae that help in collection of ovum after ovulation. It leads to wider part of oviduct called ampulla. The last part of oviduct is isthmus that has a narrow
lumen and joins the uterus.
34. Solution: (a) If the vasa efferetia in the human reproductive system get block the gametes will not be transformed from testes to epididymis.
35. Solution: (a) The testes are present in the scrotum which maintains the scrotal temperature below 2ºC of the internal body temperature.
36.Solution: (a) The signals for child birth (parturition) originate from the fully matured foetus and placenta which induce mild uterine
contractions called foetal ejection reflex.
37.Solution: (a) During fertilisation in humans, may sperms reach close to the ovum. As sperm comes in contact with the zona pellucida layer of the ovum it induces changes in the membrane that blocks the entry of additional sperm. The secretions helps one enter cytoplasmacrosome helps one sperm enter cytoplasm of ovum through zona pellucida.
38.Solution: (a) At 14th day of normal human menstrual cycle rapid secretion of LH normally occurs.
39.Solution: (d)
40.Solution: (a) The signals for child birth (parturition) originate from the fully matured foetus and placenta which induce mild uterine contractions called foetal ejection reflex.
41.Solutions : (d)
42.Solution: (d) Leydig cells found in testis is the endocrine portion of the testis which are present in between seminiferous tubules secretes
androgens or male sex hormone e.g. testosterone.
43.Solution: (a) Parturition is induced by a complex neuroendocrine mechanism. The signals for parturition originate from the fully developed foetus and the placenta which foetal ejection reflex. This triggers release of oxytocin from the maternal pituitary. : 26
44.Solution: (c) The menstrual cycle is the scientific term for the physiological changes that can occur in fertile women for the purposes of
sexual reproduction and fertilization. The secretory phase in the human menstrual cycle is also called luteal phase and lasts
for about 13 days. During secretory phase, the endometrium prepares for the implantation of an embryo and the corpus luteum is active and secretes progesterone hormone. pituitary gland is considerably reduced. The withdrawal of this hormone causes degeneration of corpus luteum and therefore, progesterone production is reduced. Production of estrogens is also reduced in this phase.
45.Solution: (d)
46.Solutions (c)Intestis, the immature aa male germ cells or spermatogenia (2n) multiple by mitotic divide and increase in number, some spermatogenia (2n) kwon as primary spermatocytes divide meoitoic division to form secondary spermatocytes (n). The secondary spermatocytes undergo to second meiotic divide to produce permatidwhich are transformed into spermatozoa (sperms) by the process called spermiogenesis.
47.Solution : (c)Function placenta – The placenta facilitates the supply of oxygen and nutrient to embryo and excretory / waste materials produced by the embryo. The placenta is connected to the embrayothrough an umbilical cord which helps inthe transport of substances to and from the embryo. Placenta also acts as an endocrine tissue and produces several hormones like human chorionic gonadotropin (hCG), human placental lactogen (hPL), estrogens, progestogens etc.
48.Solutions : (d) During embryonic development , the primary organiser signals the development of another organ or tissue by secreting
chemical factors.
49.Solution: (a) The signals for child birth (parturition) originate from the fully matured foetus and placenta which induce mild uterine
contractions called foetal ejection reflex.
50.Solution: (d)Leydig cells or interstitial cells, which are present in the intertubular spaces produce a group of hormones called androgens
mainly testosterone. Androgens play a major stimulatory role in the process of spermatogenesis (formation of spermatozoa).
51.Solution: (a) 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.
52.(d) During the embryonic development in humans. cleavage division results in a hollow ball of cells called morula. Solid mass of 32 cells foemed from zygote after successive mitotic division (after 3rd division of cleavage) is called morula.
53.(b) Inguinal canal
54.(a) female reproductive tract
55.(c) The accessory glands of the male reproductive system are the seminal vesicles, prostate gland, and the bulbourethral glands. These glands secrete fluids that enter the urethra.
56.(a) All hormones are secreted by placenta.
57.(b) ovulation is the release of the egg (ovum) from a woman’s ovary. Each month, between days six and 14 of the menstrual cycle.
Endometrial stromal cells contain lipids, glycogen, oxygen and essential minerals, which provide nutrition to developing embryo from the day of implantation (5th / 7th day of ovulation) to first eight weeks of pregnancy. Progesterone levels rise after ovulation and peak five to nine days after your luteal phase.
58.(b) LH and FSH decrease gradually during the follicular phase.
59.(d) The meiosis-II stage is completed in oogenesis only after fertilization.
60.(b) Activating
61.(d) Oestradiol levels fall after ovulation and before menstruation while, its levels peak prior to ovulation. Oestradiol are not associated with ovulation. Decrease in oestradiol level result in the cessation of menstruation.
62. (c) Corpus luteum is a mass of cells found in ovary. A corpus luteum is a mass of cells that forms in an ovary and is responsible for the production of the hormone progesterone during early pregnancy. The role of the corpus luteum depends on whether or not fertilization occurs. Sometimes, cysts can form in a corpus luteum, which can lead to painful symptoms.
63. (d) Spermatogonia are diploid cells which mature into primary spermatocytes (2/7) by growth. They then produce two haploid secondary spermatocytes by meiosis I. Each secondary spermatocyte (n) completes the meiosis II and produces two spermatids (n). Each spermatid (n) develops into a spermatozoon or sperm (n). Similarly, in females, oogonia are the diploid cells | from which through meiosis, polar bodies (n) and single ! ovum (77) are produced
64. (c) These secretions help the sperm to travel through the urethra and into the female reproductive tract. Secretions from the bulbourethral glands protect sperm and cleanse and lubricate the penile (spongy) urethra.
65.(c) Hysterectomy is the surgical removal of the uterus. It may also involve removal of the cervix, ovaries, Fallopian tubes, and other surrounding structures. Usually performed by a gynecologist, a hysterectomy may be total or partial.
66.(b) A human male ejaculates about 200-300 million sperms during a coitus of which for normal fertility at least 60% sperms must have normal shape and size and at least 40% of them must show vigorous motility.
67.(d) The main function of mammalian corpus luteum is to produce progesterone.
68.(c) the bulbourethral glands secrete an alkaline mucus-like fluid. This fluid neutralizes the acidity of the urine residue in the urethra, helps to neutralize the acidity of the vagina, and provides some lubrication for the tip of the penis during intercourse.
69.(d) Pregnancy begins with a fertilized egg. Normally, the fertilized egg attaches to the lining of the uterus. An ectopic pregnancy occurs when a fertilized egg implants and grows outside the main cavity of the uterus. An ectopic pregnancy most often occurs in a fallopian tube, which carries eggs from the ovaries to the uterus. This type of ectopic pregnancy is called a tubal pregnancy. Sometimes, an ectopic pregnancy occurs in other areas of the body, such as the ovary, abdominal cavity or the lower part of the uterus (cervix), which connects to the vagina.
70.(b) Composed of three cylindrical mass of tissue bound together by firus tissue
71. (c) A hysterectomy is surgery to completely or partially remove the womb (uterus). This is done to relieve symptoms caused by medical conditions affecting the womb.
72 (c) Capacitation is the change undergone by sperm in the female reproductive tract that enables them to penetrate and fertilize an egg.
Capacitation causes a series of signaling, biochemical and structural remodeling events that release spermatozoa from oviductal reservoir site, remodel the sperm surface, endow spermatozoa with hyperactivated motility and prepare them for interactions with the oocyte at fertilization.
73 (c) Spermiogenesis is transformation of spermatids into spermatozoa whereas spermiation is the release of the sperms from sertoli cells into the lumen of seminiferous tubule.
74 (a) The developing fetus grows in the amniotic cavity which is surrounded by the amnion. This is the membrane that covers the amniotic cavity. The membrane is derived from the extra somatic ectoderm on the inner side and mesoderm on the outer side.
75 (d) Placenta releases human chorionic gonadotropic hormone (hCG) which stimulates the Corpus luteum during pregnancy to release estrogen and progesterone and also rescues corpus luteum from regression. Human placental lactogen (hPL) is involved in growth of body of mother and breast. Progesterone maintains pregnancy, keeps the uterus silent by increasing uterine threshold to contractile stimuli.
76 (d) (a) Proliferate phase is the other name for follicular phase. There is development of the follicle in the ovary and there is increase in the endometrial cell lining in the uterus, known as proliferation. (b) The secretory phase is known as luteal phase, which includes the secretion of the hormones from the corpus luteum. This is essential for the maintenance of pregnancy. (c) Menstruation is the flow of the cell debris and the blood from the vaginal tract. This is the outcome of breakdown of the endometrial lining due to no fertilisation of the ovum.
77 (a) Extrusion of second polar body from egg nucleus occurs after entry of sperm but before fertilization. The entry of sperm into the ovum induces completion of the meiotic division of the secondary oocyte. Entry of sperm causes breakdown of metaphase promoting factor(MPF) and turns on anaphase promoting complex(APC).
78 (b) Meiotic division of the secondary oocyte is completed At the time of fusion of a sperm with an ovum.
79 (b)
• Placenta — Human Chorionic Gonadotropin (hCG)
• Zona pellucida — Layer of the ovum
• Bulbo urethral glands — Lubrication of the penis
• Leydig cells — Androgens
80(a) zona pellucida has receptors for sperm binding (ZP3 receptors) in
mammals. Corona radiata is a layer of radially arranged cells of membrana granulosa. Perivitelline space is present in between vitelline membrane and zona pellucida
81 (a) At the end of gestation, the completely developed foetus is expelled out. This process is called parturition.
Parturition is controlled by a complex neuroendocrine mechanism. Estrogen and progesterone ratio increases as estrogen levels rise significantly. Prostaglandins, which stimulate uterine contractions are also produced that act on myometrium.
Oxytocin, the main hormone, also called as birth hormone is released by maternal pituitary, which brings about strong uterine contractions. Prolactin is a lactation hormone that has no role in initiation of parturition.
82 (c) Relaxin is produced first by the corpus luteum of the ovary and later by the placenta. It helps in parturition as it increases the flexibility of the pubic symphysis and helps dilate the uterine cervix.
