Top 100+ Human Reproduction - Biology Questions and Answers For NEET 2024 Exam Preparation

Q1. The figure given below shows the sectional view of ovary. Select the option which gives correct identification of marked structure (A to D) and its feature.

1. B: Corpus luteum, it cannot be formed and added after birth.
2. A: Primary follicle, it is also called gamete mother cell.
3. C: Graafian follicle, mature follicle which ruptures to release secondary oocyte.
4. D: Tertiary follicle, a large number of this follicle degenerates during the phase from birth to puberty.

Answer: (c)

Oogonia are called as gamete mother cell. Corpus luteum is formed as a temporary endocrine structure after the ovulation. It is involved in the production of relatively high levels of progesterone and moderate levels of estradiol and inhibin A to maintain pregnancy. A large number of primary follicles degenerates during the phase from birth to puberty.

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Q2. What does 'k' represent?

1. Urinary bladder
2. Prostate
3. Seminal vesicle
4. Bulbourethral gland

Answer: (d)

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Q3. Which gland releases a small amount of fluid just prior to ejaculation to decrease acidity in the urethra caused by urine?

1. Glans penis
2. Prostate
3. Seminal vesicle
4. Bulbourethral gland

Answer: (d)

Bulbourethral gland, also called as Cowper's gland, is one of two small exocrine glands in the male reproductive system. This gland releases a small amount of fluid just prior to ejaculation to decrease the acidity in the urethra. Bulbourethral gland are homologous to Bartholin's glands present in females.

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Q4. Given below is a diagrammatic sketch of a portion of human male reproductive system. Select the correct set of the names of the parts labelled A, B, C, D

1. A. ureter, B. seminal vesicle, C. prostate, D. bulbourethral gland
2. A. vas deferens, B. seminal vesicle, C. bulbourethral gland, D. prostate
3. A. ureter, B. prostate, C. seminal vesicle, D. bulbourethral gland
4. A. vas deferens, B. seminal vesicle, C. prostate, D. bulbourethral gland

Answer: (d)

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Q5. What is indicated by 'd' in the figure?

1. Pituitary
2. Estrogen
3. LH
4. Menses

Answer: (a)

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Q6. In humans, male germs cells differentiate into _____ at the end of first meiotic division.

1. spermatogonium
2. spermatid
3. secondary spermatocyte
4. primary spermatocyte

Answer: (c)

Each primary spermatocyte duplicates its DNA and subsequently undergoes meiosis I to produce two equal, haploid secondary spermatocytes. Each of the two secondary spermatocytes further undergoes meiosis II to produce two haploid spermatids. Therefore, total four equal, haploid spermatids are produced after second meiotic division.

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Q7. ……… provide nutrition to the male germ cells.

1. Leydig cells
2. Interstitial cells
3. Sertoli cells
4. Both (a) and (b)

Answer: (c)

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Q8. Male hormone is produced in the testis by cells of

1. epithelial
2. sertoli
3. spermatocytes
4. Leydig

Answer: (d)

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Q9. In human females, meiosis-II is not complete until

1. fertilisation
2. puberty
3. uterine implantion
4. birth

Answer: (a)

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Q10. The foetal ejection reflex in humans triggers the release of

1. human chorionic gonadotropin (hCG) from placenta
2. human placental lactogen (hPL) from placenta
3. oxytocin from foetal pituitary
4. oxytocin from maternal pituitary.

Answer: (d)

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Q11. All of the following are functions of the sertoli cells in these miniferous tubules

1. they secrete inhibin, which exerts a negative feedback effect on the pituitary gland to inhibit FSH secretion.
2. they secrete an androgen-binding protein into these miniferous tubules in response to FSH stimulation.
3. they secrete mullerian-duct stimulating hormone during embryonic sexual differentiation, which results in the development of the ductus deferens.
4. they provide support for developing spermatozoa.

Answer: (c)

The sertoli cell mechanically supports developing sperm and produces androgen-binding protein, inhibin, and mullerian duct inhibitor, which causes regression of the Mullerian duct system.

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Q12. What is indicated by 'a' in the figure?

1. Menses
2. Oestrogen
3. Pituitary
4. Progesterone

Answer: (b)

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Q13. The acrosome enables the sperm to

1. produce energy for activity.
2. help in motility.
3. penetrate vitelline membrane of ovum.
4. fertilize more than one ovum.

Answer: (c)

The acrosome (head of the sperm) contains the necessary enzymes(hyaluronidase and acrosin) to penetrate the membrane of the ovum.

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Q14. Level of which hormones are at their highest during the luteal phase (second half of the cycle) of the menstrual cycle?

1. Progesterone
2. Estrogen
3. Luteinizing hormone
4. Follicular stimulating hormone

Answer: (a)

The ovulation (ovulatory phase) is followed by the luteal phase (latter phase of the menstrual cycle) during which the remaining parts of the Graafian follicle transform as the corpus luteum, which produces progesterone. So progesterone is highest at luteal phase.

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Q15. Endometrium, epithelial glands and connective tissue of uterus are broken due to the

1. lack of progesterone
2. lack of oestrogen
3. lack of FSH
4. excess of FSH

Answer: (a)

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Q16. Which of the following hormones attains a peak level in the middle of menstrual cycle?

1. FSH and progesterone
2. LH and estrogen
3. FSH and LH
4. Estrogen and progesterone

Answer: (c)

Both LH and FSH attain a peak level in the middle of menstrual cycle (about 14th day) resulting in ovulation.

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Q17. Which of the following hormone maintains the function of male sex accessory gland and ducts?

1. Androgen
2. Estrogen
3. Progesterone
4. Luteinizing hormone

Answer: (a)

Androgen is a male sex hormone which is responsible for proper functioning of male sex accessory glands and ducts.

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Q18. At what stage of life is oogenesis initiated in a human female?

1. During menarche
2. During menopause
3. At puberty
4. During embryonic development

Answer: (d)

Oogenesis is the process of formation of functional haploid ova from the diploid germinal cells in the ovary. Oogenesis begins during embryonic development but is completed only after fertilization of the secondary oocyte with the sperm.

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Q19. Match the following columns.

Codes A B C D E

1. 1 3 2 5 4
2. 5 2 4 1 3
3. 3 2 5 4 1
4. 1 2 3 4 5

Answer: (a)

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Q20. Assertion (A): The Sertoli cells are present in seminiferous tubules.

Reason (R): Sertoli cells provide nutrition to the germ cells and spermatozoa.

1. If both A and R are true, but R is not the correct explanation of the A
2. If both A and R are true and R is the correct explanation of the A
3. If A is true, but R is false
4. If A is false, but R is true

Answer: (a)

Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion. Seminiferous tubule is lined on its inside by two types of cells called male germ cells and Sertoli cells. The male germ cells form sperm and Sertoli cells provide nutrition to the germ cells.

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Q21. Cervix is a part

1. of fallopian tube
2. of kidney
3. of epididymis
4. between uterus and vagina

Answer: (d)

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Q22. Level of LH is maximum

1. just after ovulation
2. just before ovulation
3. at the time of ovulation
4. during menstrual bleeding phase

Answer: (c)

The level of LH is maximum at the time of ovulation (i.e. ovulatory phase) in the menstrual cycle. It is called as LH surge. It induces rupture of Graafian follicles and thereby the release of ovum, i.e. ovulation.

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Q23. Which of the following hormones is not a secretory product of human placenta?

1. Prolactin
2. Estrogen
3. Human chorionic gonadotropin
4. Progesterone

Answer: (a)

Prolactin is secreted by the anterior lobe of pituitary gland. After parturition, secretion and storage of milk in mammary glands is under the influence of this hormone.

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Q24. Read the given statements and select the correct option.

1. The production of sperms and ovum by the testis in males and the ovaries in female, respectively, called gametogenesis.
2. Each spermatogonium in seminiferous tubule is diploid and contains 46 chromosomes.

1. Statement I is correct, but statement II is incorrect
2. Both statements are incorrect
3. Both statements are correct
4. Statement I is incorrect, but statement II is correct.

Answer: (c)

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Q25. In artificial insemination, the semen from husband/healthy donor is artificially introduced into the ____.

1. Oviduct
2. Vagina
3. Uterus
4. Both (b) and (c)

Answer: (d)

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Q26. The correct sequence in the process of development of human embryo is

1. fertilization - cleavage - morula - zygote - blastula - gastrula
2. fertilization - zygote - blastula - morula - cleavage - gastrula
3. fertilization - zygote - cleavage - morula - blastula - gastrula
4. cleavage - zygote - fertilization - morula - blastula - gastrula

Answer: (c)

Fusion of male and female gamete produces a zygote. Repeated division of the zygote is called cleavage forming a solid morula. After further division and rearrangement a fluid filled cavity surrounded by blastomeres - blastula is formed. The appearance of germ layers mark the gastrula.

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Q27. Which is the correct path for the secretion and transport of milk in mammary gland?

1. Mammary duct → Mammary tubule → Alveoli → Lactiferous duct → Mammary ampulla → Cavity of alveoli
2. Alveoli → Cavity of alveoli → Mammary tubule → Mammary duct → Mammary ampulla → Lactiferous duct
3. Mammary duct → Cavity of alveoli → Lactiferous duct → Mammary ampulla → Mammary tubule → Alveoli
4. Alveoli → Mammary tubule → Mammary ampulla → Cavity of alveoli → Mammary duct → Lactiferous duct

Answer: (b)

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Q28. The human placenta is formed from:

1. Yolk sac
2. Amnion
3. Allantois and chorion
4. None of the above

Answer: (c)

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Q29. A gonadotropin hormone, “X” acts on interstitial cells and stimulates synthesis and secretion of “Y”. Identify X and Y from the given option.

1. X - FSH ; Y - Testosterone
2. X - LH ; Y - Androgen
3. X - TSH ; Y - Progesterone
4. X - GH ; Y - Estrogen

Answer: (b)

In males, Luteinizing hormone (LH) stimulates Leydig cell to produce androgen testosterone hormone.

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Q30. Read the following statement and answer the question. “The urethra originates from a structure (called ‘X’) and extends through the male external genitalia (called ‘Y’ which helps in introducing semen into the vagina) to its external opening called urethral meatus.” Identify X and Y.

1. X - Vas efferentia ; Y - Penis
2. X - Urinary bladder ; Y - Penis
3. X - Ejaculatory duct ; Y - Ureter
4. X - Bulbourethral gland ; Y - Ureter

Answer: (b)

The urethra originates from a structure [called urinary bladder (X)] and extends through the male external genitalia [called penis (Y) which helps in introducing semen into the vagina) to its external opening called urethral meatus.

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Q31. How many ovum(s) is/are released in one menstruation?

1. 2
2. 1
3. 3
4. 4

Answer: (b)

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Q32. How many germinal layers does embryo consist of initially, after implantation?

1. 2
2. 3
3. 4
4. 5

Answer: (a)

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Q33. Morula is a developmental stage

1. between the blastocyst and gastrula
2. between the zygote and blastocyst
3. after the implantation
4. between implantation and parturition

Answer: (b)

The embryo with 8-16 blastomeres is called a morula. It is an embryonic developmental stage between the zygote and the blastocyst.

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Q34. The part of Fallopian tube closest to the ovary is

1. Infundibulum
2. Isthmus
3. Cervix
4. Ampulla

Answer: (a)

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Q35. The part of Fallopian tube closest to the ovary is

1. infundibulum
2. cervix
3. isthmus
4. ampulla

Answer: (a)

Each fallopian tube is about 10-12 cm long and extends from the periphery of each ovary to the uterus, the part closer to the ovary is the funnel-shaped infundibulum. The edges of the infundibulum possess finger-like projections called fimbriae, which help in collection of the ovum after ovulation. The infundibulum leads to a wider part of the oviduct called ampulla. The last part of the oviduct, isthmus has a narrow lumen and it joins the uterus.

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Q36. Capacitation occurs in :

1. Vas deferens
2. Epididymis
3. Female reproductive tract
4. Rete testis

Answer: (c)

Capacitation is increase in fertilising capacity of sperms which occurs in female reproductive tract. It is required to render sperm to fertilize an oocyte.

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Q37. The main function of mammalian corpus luteum is to produce

1. progesterone only
2. oestrogen only
3. human chorionic gonadotropin
4. relaxin only

Answer: (a)

The main function of mammalian corpus luteum is the secretion of progesterone, which is essential for the maintenance of endometrium.

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Q38. Which of the following induces foetal ejection reflex?

1. Fully developed foetus and placenta
2. Initiation of lactation
3. Expulsion of the baby out of the uterus.
4. Transport of embryo in the fallopian tube.

Answer: (a)

Fully developed foetus and the placenta induce foetal ejection reflex. Foetal ejection reflex is also called mild uterine contraction.

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Q39. What does 'e' represent in the figure?

1. Oogonium
2. Ovum
3. Mature follicle
4. Zona pellucida

Answer: (b)

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Q40. Part of sperm involved in penetrating egg membrane is –

1. Acrosome
2. Tail
3. Allosome
4. Autosome

Answer: (a)

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Q41. Which one of the following is not a male accessory gland?

1. Mammary gland
2. Seminal vesicle
3. Prostate
4. Bulbourethral gland

Answer: (a)

Mammary gland is a part of female reproductive system. Rest are the male accessory glands.

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Q42. Uterus is commonly known as

1. Womb
2. Birth canal
3. Primary female sex organ
4. Female external genitalia

Answer: (a)

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Q43. Menstrual flow occurs due to the lack of

1. FSH
2. progesterone
3. oxytocin
4. vasopressin

Answer: (b)

Menstrual flow occurs due to the lack of progesterone. Progesterone is secreted by corpus luteum and is essential for the maintenance of endometrium. In the absence of progesterone, the endometrium starts to degenerate. This leads to menstrual flow in which the endometrial wall gets shed off.

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Q44. In human adult females oxytocin

1. causes strong uterine contractions during parturition
2. is secreted by anterior pituitary
3. stimulates pituitary to secrete vasopressin
4. stimulates growth of mammary glands

Answer: (a)

In human adult female, oxytocin is a hormone released by the pituitary gland (neurohypophysis) that causes contraction of the uterus during labour and stimulates milk flow from the breasts by causing contraction of muscle fibres in the milk ducts.

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Q45. What does 'a' represent in the figure?

1. Sperm
2. Cells of corona radiata
3. Perivitelline space
4. Zona pellucida

Answer: (d)

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Q46. The reproductive cycle in the female primates such as monkeys, apes and human beings is called

1. oestrus cycle
2. menstrual cycle
3. circadian cycle
4. ovulatory cycle

Answer: (b)

The rhythmic series of changes that occurs in the reproductive organs of female primates like monkeys, apes and human beings, is called menstrual cycle. It is repeated at an average interval of about 28/29 days.

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Q47. All copulations do not lead to pregnancy. The most appropriate reason to support this statement is

1. The ovum and sperm should be continuously transported to ampullary-isthmic junction.
2. The ovum and sperm should be transported randomly to ampullary-isthmic junction.
3. The ovum and sperm should be simultaneously transported to ampullary- isthmic junction.
4. None of these

Answer: (c)

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Q48. The menstrual flow in menstrual cycle lasts for about

1. Almost 7 days
2. 6 to 7 days
3. 3 to 5 days
4. 1 to 2 days

Answer: (c)

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Q49. The difference between primary and secondary spermatocyte lies in ____.

1. Number of chromosomes
2. Presence/absence of a tail
3. Being hormone producing/non-hormone producing
4. Primary gamete/secondary gamete in males

Answer: (a)

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Q50. Semen consists of

1. Seminal plasma + Spermatozoa
2. Seminal plasma + Spermatid
3. Seminal plasma + Spermatogonia
4. None of these

Answer: (a)

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Q51. Which one of the following is the correct matching of the events occurring during menstrual cycle?

1. Secretory phase : Development of corpus luteum and increased secretion of progesterone
2. Menstruation : Breakdown of myometrium and ovum not fertilised
3. Proliferative phase : Rapid regeneration of myometrium and maturation of Graafian follicle
4. Ovulation : LH and FSH attain peak level and sharp fall in the secretion of progesterone

Answer: (a)

Secretory phase is also called as luteal phase. The luteinising hormone or LH is secreted by the anterior lobe of pituitary gland. LH causes ovulation. LH stimulates cells of ovarian follicles to develop corpus luteum. Corpus luteum secretes large amount of progesterone.

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Q52. What is indicated by 'c' in the figure?

1. Second follicle
2. Primary follicle
3. Tertiary follicle
4. Graafian follicle

Answer: (c)

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Q53. Which of the following does not occur in the time during and immediately following fertilization?

1. Division of the oocyte cell by meiosis
2. Fusion of the sperm and ovum nuclei.
3. Implantation of the ovum in the uterus.
4. Digestion of cell layers around the oocyte by sperm.

Answer: (c)

Implantation is not the immediate process. It takes 5 days to occur after fertilization.

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Q54. Which of the following statements is correct?

1. Oogenesis is initiated during the embryonic developmentstage .
2. At puberty only 60, 000-80, 000 primary follicles are left in each ovary.
3. The primary follicles surrounded with manylayers of granulosa cells and form a new theca called secondary follicles.
4. Changing of sanitary napkins or pads after every 4-5 hours is necessary for maintaining menstrual hygiene.

1. I, II, III and IV
2. I and II
3. I and III
4. None of these

Answer: (a)

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Q55. Which one of the following is not the function of placenta? It

1. facilitates removal of carbon dioxide and waste material from embryo.
2. secretes estrogen
3. secretes oxytocin during parturition
4. facilitates supply of oxygen and nutrients to embryo

Answer: (c)

Function of placenta – The placenta facilitate the supply of oxygen and nutrients to the embryo and also removal of carbon dioxide and excretory/waste materials produced by the embryo. The placenta is connected to the embryo through an umbilical cord which helps in the 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, progesterone etc.

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Q56. The primary oocytes are in which stage of cell division?

1. Prophase I of meiotic division
2. Prophase I of mitotic division
3. Prophase II of meiotic division
4. Prophase II of mitotic division

Answer: (a)

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Q57. The testes are situated ____ the abdominal cavity within a pouch called ____.

1. outside, scrotum
2. inside, testicular lobules
3. outside, vas deferens
4. inside, scrotum

Answer: (a)

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Q58. Which of the following is required for the increased production of estrogen, progestogens, cortisol, prolactin and thyroxine etc. in the maternal blood?

1. Metabolic changes in the mother.
2. Maintenance of pregnancy.
3. Supporting the foetal growth
4. Destruction of Graafian follicle

1. (i), (iv) and (v)
2. (iii) and (iv)
3. (i), (ii) and (iii)
4. All the four statements.

Answer: (c)

During pregnancy, the increased production of the levels of hormones like estrogen, progestogens, cortisol, prolactin, thyroxine in the maternal blood are essential for supporting the foetal growth, metabolic changes in the mother and maintenance of pregnancy.

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Q59. An adult testes bears ____ compartments called testicular lobules.

1. 250
2. 150
3. 350
4. 500

Answer: (a)

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Q60. Statement 1 : Implantation is the process of attachment of blastocyst on uterine endometrium.

Statement 2 : Implantation is controlled by trophoblast and occurs by decidual cell reaction.

1. Statement -1 is True, Statement -2 is True ; Statement-2 is NOT a correct explanation for Statement – 1
2. Statement- 1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement -1
3. Statement - 1 is True, Statement- 2 is False
4. Both the Statements are False.

Answer: (a)

The process of attachment of the blastocyst (mammalian blastula) on the endometrium of uterus is called implantation.

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Q61. Eye lens is formed from

1. mesoderm
2. endoderm
3. ectoderm
4. ectoderm and mesoderm.

Answer: (c)

Ectoderm, mesoderm and endoderm are the three germ layers that give rise to the specific tissues, organs and organ-systems. Ectoderm gives rise to conjunctiva, cornea, lens of eye, muscles of iris, vitreous humour, retina, lacrimal gland along with other parts of the body.

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Q62. Which of the following is the first change that occurs to the zygote after fertilization?

1. It begins to secrete the hormones.
2. It divides to form a hollow ball of cells, called the blastocyst.
3. It contacts the endometrial wall of the uterus and becomes buried inside it.
4. It initiates the formation of a placenta.

Answer: (b)

The zygote divides mitotically to form 8, 16 daughter cells called blastomeres. This stage is called morula which continues to divide and transforms into blastocyst.

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Q63. Gonads develop from embryonic

1. endoderm
2. mesoderm
3. ectoderm
4. both mesoderm and endoderm

Answer: (b)

Gonads, muscles, dermis, kidneys, etc., develop from mesoderm. Ectoderm produces epidermis, glands, nervous system, etc. Pancreas, lining of urinary bladder, etc., develop from endoderm.

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Q64. Spermatogonium undergoes ____.

1. Meiotic division
2. Reduction division
3. Mitotic division
4. None of these

Answer: (c)

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Q65. The uterus opens into vagina through ____.

1. Isthmus
2. Ampulla
3. Cervix
4. Labia minora

Answer: (c)

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Q66. Assertion: Clitoris is not remnant of penis in females.

Reason: It also have high blood supply and erectile tissue.

1. If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion.
2. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
3. If Assertion is true but Reason is false.
4. If both Assertion and Reason are false.

Answer: (c)

Clitoris is a female reproductive organ. It is homologous to penis of males. It is not remnant of penis. It is devoid of erectile tissue and high blood supply as present in penis. Penis is the copulatory organ of males.

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Q67. Identify the structure marked as “X” and its function in the given figure of male reproductive system.

1. Bulbourethral gland: It secretes alkaline mucus for lubricating the reproductive tract.
2. Rete testis: It helps seminiferous tubule to open into vas efferentia.
3. Vas efferentia: They have contractile mechanism that aids in the emission of seminal fluid.
4. Seminal vesicle: It synthesizes and secrete testicular hormone.

Answer: (b)

The structure marked as X is rete testis. The rete testis is an anastomosing network of delicate tubules located in the hilum of the testicle (mediastinum testis) that carries sperm from the seminiferous tubules to the efferent ducts.

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Q68. Seminal plasma, the fluid part of semen, is contributed by

1. Seminal vesicle
2. Prostate
3. Urethra
4. Bulbourethral gland

1. I, II and IV
2. I and II
3. II, III and IV
4. I and IV

Answer: (a)

The male accessory glands are paired seminal vesicles, a prostate and paired bulbourethral glands. Secretions of these glands constitute the seminal plasma that is rich in fructose, calcium and certain enzymes. The secretions of bulbourethral glands also help in the lubrication of penis.

Urethra is the duct that extends through the penis in male reproductive system and serve as a common passage for both sperm and urine. In female, urethra has more productive function.

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Q69. Female produces only

1. One type of gamete X
2. One type of gamete Y
3. Either X or Y type of gamete
4. All of these

Answer: (a)

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Q70. In humans, at the end of the first meiotic division, the male germ cells differentiate into the

1. secondary spermatocytes
2. primary spermatocytes
3. spermatids
4. spermatozonia

Answer: (a)

In human, at the end of the first meiotic division, the male germ cells differentiate into the secondary spermatocytes.

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Q71. A change in the amount of yolk and its distribution in the egg will affect

1. number of blastomeres produced
2. fertilization
3. pattern of cleavage
4. formation of zygote.

Answer: (c)

Cleavage is a series of cell divisions by which a single fertilized egg cell is transformed into a multicellular body, the blastula. Characteristically no growth occurs during cleavage, the shape of the embryo is unchanged except for the formation of central cavity (the blastocoel), and the ratio of nuclear material (DNA) to cytoplasm increases.

The mode of cleavage is determined by the amount of yolk and its distribution. On this basis cleavage may be holoblastic and meroblastic.

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Q72. Assertion (A): The bulbourethral gland is a male accessory gland.

Reason (R): Its secretion helps in the lubrication of the penis, thereby facilitating reproduction.

1. If both A and R are true, but R is not the correct explanation of the A
2. If both A and R are true and R is the correct explanation of the A
3. If A is true, but R is false
4. If A is false, but R is true

Answer: (b)

Both Assertion and Reason are true and Reason is the correct explanation of Assertion. The bulbourethral gland is a male accessory gland. Its secretions help in lubricating the penis to facilitate reproduction.

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Q73. The anatomical structure which succeeds infundibulum is

1. Ampulla
2. Isthmus
3. Uterus
4. Ovary

Answer: (a)

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Q74. Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female?

1. Maintenance of high concentration of sex- hormones in the blood stream
2. Retention of well-developed corpus luteum
3. Maintenance of the hyper trophical endometrial lining
4. Fertilisation of the ovum

Answer: (a)

High concentration of sex steroids (estrogen) exerts negative feedback on anterior pituitary, decreasing LH secretion and release thus, lowering LH level in blood. Due to insufficient LH level no ovulation occurs which causes irregular menstruation.

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Q75. Identify the odd one from the following.

1. fimbriae
2. labia minora
3. infundibulum
4. isthmus

Answer: (b)

The female accessory ducts constitute the oviducts(Fallopian tubes), uterus and vagina. Each fallopian tube extends from the periphery of each ovary to the uterus.

The closer part of the ovary is the funnel-shaped infundibulum, that possess finger-like projections called fimbriae. The infundibulum leads to a wider part of the oviduct called ampulla. The last part of the oviduct is isthmus. While, labia minora is the female external genitalia.

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Q76. Eye lens is formed from

1. mesoderm
2. endoderm
3. ectoderm
4. ectoderm and mesoderm

Answer: (c)

Ectoderm, mesoderm and endoderm are the three germ layers that give rise to the specific tissues, organs and organ-systems. Ectoderm gives rise to conjunctiva, cornea, lens of eye, muscles of iris, vitreous humour, retina, lacrimal gland along with other parts of the body.

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Q77. The middle piece of the sperm contains

1. mitochondria
2. centriole
3. proteins
4. nucleus.

Answer: (a)

The sperm consists of head, neck, middle piece and tail. The middle piece of human sperm contains the mitochondria coiled around the axial filament called mitochondrial spiral. They provide energy for the movement of the sperm.

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Q78. Which of the following is not a uterine function?

1. Nutritional support of the growing embryo.
2. Waste removal for the developing embryo.
3. Place of fusion of male and female gametes.
4. Mechanical protection of the developing embryo.

Answer: (c)

Male and female gametes are fused in ampullary isthmic junction of fallopian tube. Fusion of gametes is not the function of uterine wall.

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Q79. Which one of the following are rich in fructose, calcium and some enzymes?

1. Liver
2. Pancreas
3. Male accessory glands
4. Salivary glands

Answer: (c)

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Q80. Given below is a diagrammatic sketch of a portion of human male reproductive system. Select the correct set of the names of the parts labelled A, B, C, D.

1. A-Vas deferens, B-Seminal vesicle, C-Bulbourethral gland, D-Prostate
2. A-Ureter, B-Seminal vesicle, C-Prostate,D-Bulbourethral gland
3. A-Vas deferens, B-Seminal vesicle, C-Prostate, D-Bulbourethral gland
4. A-Ureter, B-Prostate, C-Seminal vesicle, D-Bulbourethral gland

Answer: (c)

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Q81. Ectopic pregnancies are referred to as

1. pregnancies terminated due to hormonal imbalance
2. pregnancies with genetic abnormality
3. implantation of defective embryo in the uterus
4. implantation of embryo at site other than uterus

Answer: (d)

Ectopic pregnancy is a complication of pregnancy in which implantation of embryo takes place at site other than uterus. Signs and symptoms include abdominal pain and vaginal bleeding. Most ectopic pregnancies (90%) occur in the fallopian tube, which are known as tubal pregnancies.

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Q82. During parturition, the mild uterine contractions which lead to expulsion of the foetus is known as

1. Foetal ejection reflex
2. Foetal ejection release
3. Foetal uterine reflex
4. Foetal placental reflex

Answer: (a)

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Q83. If for some reason, the vasa efferentia in the human reproductive system gets blocked, the gametes will not be transported from

1. epididymis to vas deferens
2. testes to epididymis
3. ovary to uterus
4. vagina to uterus

Answer: (b)

If the vasa efferentia in the human reproductive system get blocked the gametes will not be transformed from testes to epididymis.

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Q84. The figure given below shows the sectional view of seminiferous tubule. A B C D Which marked structure (A to D) undergoes second meiotic division to produce four equal haploid cells (called spermatids)?

1. B
2. A
3. C
4. D

Answer: (a)

'B' are the secondary spermatocytes which further undergoes meiosis II to produce two haploid spermatids.

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Q85. About which day in a normal human menstrual cycle does rapid secretion of LH (Popularly called LH-surge) normally occur?

1. 20th day
2. 14th day
3. 5th day
4. 11th day

Answer: (b)

At $14^{th}$ day of normal human menstrual cycle rapid secretion of LH normally occurs.

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Q86. A sectional view of mammary gland shows

1. nipple and areola.
2. mammarylobes (alveolus) and duct.
3. ribs.
4. ampulla and lactiferous duct.

Choose the correct option from the above.

1. I, II and III
2. I, II, III and IV
3. III, IV and II
4. I, IV and III

Answer: (b)

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Q87. Secondary oocyte develops zona pellucida around it in the ____.

1. Secondary follicle
2. Primary follicle
3. Tertairy follicle
4. Graafian follicle

Answer: (d)

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Q88. Which of the following contains a fluid filled cavity called antrum?

1. Primary follicle of ovary.
2. Primary spermatocyte.
3. Tertiary follicle of ovary.
4. Secondary spermatocyte.

Answer: (c)

In biology, antrum is a general term for a cavity or chamber, which may have specific meaning in reference to certain organs or sites in the body.Tertiary follicle of ovary contains a fluid filled cavity called antrum and a secondary oocyte ready for ovulation.

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Q89. Structure connecting the foetus to placenta is

1. amnion
2. umbilical cord
3. yolk sac
4. chorion

Answer: (b)

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Q90. Which extraembryonic membrane in humans prevents desiccation of the embryo inside the uterus?

1. Amnion
2. Chorion
3. Yolk sac
4. Allantosis

Answer: (a)

Amnion is a type of extraembryonic membrane formed by the amniogenic cells inside and splanchnopleuric extraembryonic mesoderm outside. Amnion surrounds the embryo creating the amniotic cavity that is filled with amniotic fluid. The amniotic fluid serves as a shock absorber for the fetus, regulates fetal body temperature and prevents desiccation.

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Q91. The second trimester of human pregnancy is characterized by

1. Appearance of external genital organs
2. Appearance of heart and aorta
3. Appearance of fine hair, eye-lashes on the eye-lids
4. Appearance of limbs and digits

Answer: (c)

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Q92. Which of the following is a finger like structure and lies at the upper junction of the two labia minora above the urethral opening?

1. Oviduct
2. Clitoris
3. Ampulla
4. Chorionic villi

Answer: (b)

Clitoris is a small, sensitive, erectile part of the female genitals at the anterior end of the vulva. It is homologous with the penis.

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Q93. Placenta is formed in humans by

1. allantois
2. amnion
3. chorion
4. All of these

Answer: (c)

Human placenta is largely formed of chorion and contains blood vessels formed by allantois.

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Q94. Chorionic villi and uterine tissue become interdigitated with each other and jointly form

1. inner cell mass
2. trophoblast
3. placenta
4. embryo

Answer: (c)

Chorionic villi and uterine tissue become interdigitated with each other and jointly form a structural and functional unit between the developing embryo and the maternal body. This structure is called placenta.

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Q95. The sex of the foetus will be decided at

1. implantation
2. fertilisation by male gamete
3. fertilisation by female gamete
4. the start of cleavage

Answer: (b)

The sex of the foetus will be decided at fertilisation by male gamete. The chromosome pattern in the human female is XX and in the male is XY. If the sperm carrying X-chromosome fertilises the ovum, the zygote would develop into a female and if Y fertilises the ovum, the zygote would be a male.

Thus, the sex of the foetus depends on the type of chromosome present in male gamete which fertilises the egg.Zygote divides rapidly by mitotic division when it moves through the isthmus of the oviduct towards the uterus. This rapid division is called cleavage.

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Q96. Extrusion of second polar body from egg nucleus occurs

1. after completion of fertilization
2. after entry of sperm but before completion of fertilization
3. before entry of sperm
4. without any relation of sperm entry

Answer: (b)

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Q97. Middle piece of mammalian sperm possesses

1. mitochondria only
2. mitochondria and centriole
3. centriole only
4. nucleus and mitochondria

Answer: (a)

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Q98. Match Column -I with Column - II.

1. A-(4); B-(2); C-(3); D-(1)
2. A-(2); B-(1); C-(4); D-(3)
3. A-(4); B-(3); C-(2); D-(1)
4. A-(4); B-(3); C-(1); D-(2)

Answer: (b)

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Q99. Which of the following cells during gametogenesis is normally diploid?

1. Spermatogonia
2. Spermatid
3. Secondary polar body
4. Primary polar body

Answer: (a)

During gametogenesis, spermatogonia are diploid be-cause of undergoing the process of meiosis.

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Q100. Morula divides and transforms into

1. Blastocyst
2. Inner cell mass
3. Trophoblast
4. Blastomere

Answer: (a)

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