Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Cell culture wikipedia , lookup
Embryonic stem cell wikipedia , lookup
State switching wikipedia , lookup
Microbial cooperation wikipedia , lookup
Somatic cell nuclear transfer wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Adoptive cell transfer wikipedia , lookup
Regeneration in humans wikipedia , lookup
Sexual reproduction wikipedia , lookup
Chimera (genetics) wikipedia , lookup
Cell theory wikipedia , lookup
1 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) HUMAN REPRODUCTION 1. Which one is a primary sex organ? a) Penis b) Testis c) Prostate d) Scrotum Ans. (b) 2. Which of the following is secondary sex organ? a) Beard b) Uterus c) Ovary d) Broad hips Ans. (b) 3. An accessory sex character is : a) fallopian tubes b) beard c) pituitary d) ovary Ans. (b) 4. Scrotal sacs are connected with abdominal cavity by: a) Epididymis b) Spermatic canal c) Inguinal canal d) Haversian canal Ans. (c) 5. In many mammals, testes remain outside body cavity in scrotal sacs because: a) It helps in coitus b) It helps in ejection of semen c) sperms produced in it are more active. d) spermatogenesis occurs at a temperature lower than that of body. Ans. (d) 6. In which of the following organisms testes descends into scrotum in breeding season but in non-breeding season goes up? a) Bat b) Frog c) Whale d) Seal Ans. (a) 7. In mammals, failure of testes to descend into the scrotum is known as : a) castration b) impotency c) paedogenesis d) cryptorchidism Ans. (d) 8. Gubernaculum is the ligamentous connective cord which connects: a) testis to kidney b) testis to scrotum c) ovary to abdominal wall d) muscle to muscle Ans. (b) 9. Mesorchium refers to: a) capsule in testis b) capsule in ovary c) a peritoneal fold that covers testis d) a peritoneal fold that connects ovary and kidney Ans. (c) 10. The tunica albuginea is a covering around the: a) testes b) kidneys c) uterus Ans. (a) d) epididymis 11. Sperms are produced in : a) vas deferens b) epididymis c) interstitial cells d) seminiferous tubules Ans. (d) 12. Which of the following is found in the interstitial connective tissue of testis? a) Sertoli cells b) Sustencular cells c) Leydig cells d) Germ cells Ans. (c) 13. Leydig cells produce: a) sperms b) testosterone c) progesterone d) corticosterone Ans. (b) 14. Testosterone is a/an: a) steroid b) protein c) octapeptide d) glycoprotein Ans. (a) 15. The primary regulator of Leydig cell secretion is: a) FSH releasing factor b) Androgen-binding protein c) Luteinizing hormone (LH) d) Follicle stimulating hormone Ans. (c) 16. Supporting cells found in between the germinal epithelium of testis are called: a) Phagocytes b) Sertoli cells c) Leydig cells d) Granular cells Ans. (b) 17. In the vertebrate testes, for nourishment during spermiogenesis, the spermatids get attached to: a) Sertoli cells b) Spermatocytes c) Interstitial cells d) Sperm-mother cells Ans. (a) 18. Sertoli cells are found in testis. These cells are: a) nurse cells b) reproductive cells c) receptor cells d) none of these Ans. (a) 19. Which of the following controls the function of Sertoli cells? a) FSH b) ICSH c) Oestrogen d) Testosterone Ans. (a) 20. Rete testis opens to: 2 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) Urethra b) Vasa efferentia c) Bidder’s canal d) Cauda epididymis Ans. (b) 21. The head of epididymis is called: a) vas deferens b) gubernaculum c) caput epididymis d) cauda epididymis Ans. (c) 22. Cauda epididymis leads to: a) rete testis b) vas efferens c) vas deferens d) ejaculatory duct Ans. (c) 23. The main function of vas deferens is to: a) store the sperms b) mature the sperms c) conduct the sperms d) none of these Ans. (c) 24. Major part of semen is secreted by: a) Seminal vesicle b) Prostate gland c) Cowper’s gland d) Bartholin’s gland Ans. (a) 25. The common duct formed by the union of vas deferens and duct from seminal vesicle is: a) Urethra b) Stenson’s duct c) Spermatic duct d) Ejaculatory duct Ans. (d) 26. Which gland in mammal makes alkaline secretion for lubrication? a) Testis b) Pineal body c) Cervical glands d) Cowper’s gland Ans. (d) 27. In rabbit, the acidity in the urethra is neutralized by the secretions of: a) cowper’s glands b) Bartholin glands c) perineal glands d) Leydig cells Ans. (a) 28. The skin covering the glans penis is called: a) Prepuce b) Epididymis c) corpora cavernosa d) corpus spongiosum Ans. (a) 29. Corpora cavernosa are found in: a) testis b) ovary c) penis d) uterus Ans. (c) 30. Seminal plasma contains the secretions of: a) Follicles, uterus and prostate gland b) Prostate, Cowper’s and Bartholin’s gland c) Seminal vesicle, uterus and prostate gland d) Seminal vesicle, prostate and Cowper’s gland Ans. (d) 31. Which one is unpaired gland in male reproductive system? a) Seminal vesicle b) Cowper’s gland c) Prostate gland d) Lacrimal gland Ans. (c) 32. Prostate gland is a: a) Digestive gland b) Sperm producing gland c) Hormone producing gland of males d) Semen secreting accessory gland of male Ans. (d) 33. Which of the following sugars in semen is a source of energy for the spermatozoa? a) Sucrose b) Fructose c) Glucose d) Galactose Ans. (b) 34. Sugar fructose is present in the secretion of: a) seminal vesicles b) Cowper’s gland c) Perineal gland d) Bartholin’s gland Ans. (a) 35. Semen contains all of the following except: a) Mucus b) Fructose c) Substances to reduce the pH of the vaginal environment d) Substances to increase the motility of the uterine muscles Ans. (c) 36. At what speed a human sperm moves in the female genital tract? a) 3 mm/min b) 10 mm/min c) 15 mm/min d) 20 mm/min Ans. (a) 37. Match the following: Set I Set II A Inguinal canal 1. Network of channels after seminiferous tubules B Rete testis 2. Secondary sexual characters C Leydig cells 3. For descending of testis D Prepuce 4. Dorsal bundles of spongy tissue E Corpora 5. Terminal skin of penis cavernosa Answer codes: a) A = 1, B = 2, C = 3, D = 5, E = 4 b) A = 3, B = 1, C = 4, D = 2, E = 5 c) A = 2, B = 4, C = 3, D = 5, E = 1 d) A = 3, B = 1, C = 2, D = 5, E = 4 Ans. (d) 38. 3 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) A-oviduct, B-uterus, C-outduct, D-ovary b) A-cervix, B-uterus, C-ovary, D-tumour c) A-uterus, B-uterine cavity, C-oviducal funnel, D-ovary d) A-cervix, B-uterus cavity, C-fallopian tube, D-ovary Ans. (d) 39. In a Graafian follicle : a) eggs are fertilized b) there are many oocytes c) there are many sperms d) there is a single oocyte Ans. (d) 40. Cumulus covers: a) ovum b) ovary c) embryo d) all of these Ans. (a) 41. Antrum is the cavity of: a) Ovary b) Blastula c) Gastrula d) Graafian follicle Ans. (d) 42. A glycoprotein non-cellular membrane which normally surrounds the ovum of a mammal: a) corona radiata b) jelly envelope c) zona pellucida d) granulosa membrane Ans. (c) 43. Ovulation occurs under the influence of: a) LH b) Estrogens c) FSH d) Progesterone Ans. (a) 44. Which one holds corona radiata cells together? a) Lipoprotein b) Liposaccharide c) Oligosaccharide d) Mucopolysaccharide Ans. (d) 45. Which is the correct sequence of layers in the mammalian egg from outside to inside? a) Zona pellucida, corona radiata, plasma membrane b) Corona radiata, zona pellucida, plasma membrane c) Plasma membrane, zona pellucida, corona radiata d) None of the above Ans. (b) 46. When is progesterone mainly secreted? a) After ovulation b) After parturition c) Before ovulation d) At the time of parturition Ans. (a) 47. The mammalian corpus luteum produces: a) FSH b) progesterone c) luteinizing hormone d) HCG Ans. (b) 48. Which of the following statements is correct? a) Corpus luteum changes into corpus albicans b) Corpus luteum degenerates after fertilization c) Corpus luteum grows throughout the pregnancy d) Corps luteum is not formed during the pregnancy Ans. (a) 49. Both corpus luteum and macula lutea are: a) a source of hormones b) found in human ovaries c) characterized by a yellow colour d) contributory in maintaining pregnancy Ans. (c) 50. Expanded proximal part of oviduct is: a) uterus b) isthmus c) vestibule d) fimbriated funnel Ans. (d) 51. Which one of the following is out of place? a) Ureter b) Vagina c) Uterus d) Oviduct Ans. (a) 52. Mark the series with odd: a) Endometrium, graafian follicle, polar body b) Spermatocyte, prostate, spermatid, acrosome c) Ovaries, vagina, Batholin’s gland, corpus luteum d) Vas deferens, Fallopian tube, epididymis, Cowper’s gland Ans. (d) 53. The cellular layer that disintegrates and regenerates again and again in humans is: a) dermis of skin b) cornea of the eye c) endometrium of uterus d) endothelium of blood vessels Ans. (c) 54. Bartholin’s glands occur in: a) Males and form liquid part of semen b) Females and help in vestibular lubrication 4 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) c) Males and produce alkaline fluid for neutralizing urethral acidity d) Females and produce estrogen for regulating secondary sexual characters Ans. (b) 55. Bartholin’s glands of female correspond to which glands in male? a) Rectal glands b) Inguinal glands c) Prostate glands d) Cowper’s glands Ans. (d) 56. Vaginal orifice and urethral orifice open into: a) cervix b) vulva c) labia majora d) labia minora Ans. (b) 57. Labium majora of a female mammal is homologous to: a) scrotal sac b) prostate gland c) epididymis d) seminal vesicle Ans. (a) 58. Which of the following is unpaired in a mammal? a) Ovary b) Clitoris c) Fallopian tube d) Cowper’s gland Ans. (b) 59. The starting of menstruation in girls is: a) puberty b) menarche c) climacteric d) menopause Ans. (b) 60. The phase of menstrual cycle in humans that lasts for 3-4 days is: a) luteal phase b) menstruation c) ovulatory phase d) follicular phase Ans. (b) 61. Ovary secretes large quantity of estrogen during: a) menopause b) lactation c) preovulatory period d) menstrual phase Ans. (c) 62. Which of the following hormones is active during proliferative phase of menstrual cycle? a) Estrogen b) Progesterone c) Testosterone d) All of these Ans. (a) 63. Progesterone hormone is active during: a) follicular phase b) secretory phase c) menstrual phase d) proliferative phase Ans. (b) 64. In the absence of pregnancy, corpus luteum: a) degenerates after some time b) is maintained by progesterone c) becomes active, secretes FSH and LH d) produces a lot of oxytocin and relaxin Ans. (a) 65. In human female, which of the following is incorrect? a) Menstruation takes 4 days b) Menstrual cycle takes 28 days c) Menopause occur at an age of 45-55 years d) The ovulated eggs released during pregnancy die Ans. (d) 66. Cessation of menstrual cycle is termed: a) menarche b) menopause c) impotency d) puberty Ans. (b) 67. After menopause there is a rise in urinary excretion of: a) FSH b) STH c) Oxytocin d) Oestrogen Ans. (a) 68. Estrous cycle is characteristic of: a) all mammals b) human females c) mammalian females d) non-primate mammalian females Ans. (d) 69. Estrous period is an indication of: a) pregnancy b) breeding period c) menopause d) estrogen secretion Ans. (b) 70. Which of the following are supposed to be immortal? a) Brain cells b) Germ cells c) Pituitary cells d) All of these Ans. (b) 71. Which type of cell division occurs in the gonads? a) Mitosis only b) Meiosis only c) Amitosis and meiosis d) Both mitosis and meiosis Ans. (d) 72. If a germ cell in a female gonad and a germ cell in a male gonad begin undergoing meiosis simultaneously, what will be the ratio of ova and sperms produced? a) 1 : 1 b) 1 : 2 c) 1 : 4 d) 2 : 1 Ans. (c) 73. By which cell division spermatogonia are formed? a) Mitosis b) Amitosis c) Meiosis I d) Meiosis II Ans. (a) 74. Spermatogenesis is mainly promoted by: a) FSH b) MSH c) ACTH d) none of the above 5 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) Ans. (a) 75. Correct sequence of cell stages in spermatogenesis is: a) spermatocytes, spermatids, spermatogonia, spermatozoa b) spermatogonia, spermatocytes, spermatids, spermatozoa c) spermatocytes, spermatogonia, spermatids, spermatozoa d) spermatogonia, spermatids, spermatocytes, spermatozoa Ans. (b) 76. In spermatogenesis, the phase of maturation involves: a) The growth of spermatogonia into primary spermatocyte b) The formation of spermatogonia from gonocytes through mitosis c) The formation of spermatids from primary spermatocytes through meiosis d) The formation of spermatogonia from the spermatocytes through meiosis Ans. (c) 77. Which one of the following pairs is diploid? a) Spermatid and sperm b) Spermatogonia and spermatid c) Primary and secondary spermatocytes d) Spermatogonia and primary spermatocyte Ans. (d) 78. Which of the following are haploid in nature? 1) Spermatids 2) Spermatogonia 3) Primary spermatocytes 4) Secondary spermatocytes Answer codes: a) 1 and 2 are correct b) 1 and 4 are correct c) 2 and 4 are correct d) 1, 2 and 3 are correct Ans. (b) 79. Number of spermatozoa produced by a single secondary spermatocyte during spermatogenesis is: a) one b) two c) four d) eight Ans. (b) 80. Sperms formed from four primary spermatocytes are: a) 1 b) 4 c) 16 d) 32 Ans. (c) 81. How many secondary spermatocytes are required to form 400 spermatozoa? a) 40 b) 100 c) 200 d) 400 Ans. (c) 82. Conversion of spermatid to a spermatozoan is called: a) cytokinesis b) vitellogenesis c) spermiogenesis d) spermatogenesis Ans. (c) 83. In the given diagram identify parts named 1 – 5: a) 1-nucleus, 2-tail, 3-mitochondria, 4acrosome, 5-centriole b) 1-acrosome, 2-nucleus, 3-centriole, 4mitochondria, 5-plasma membrane c) 1-nucleus, 2-mitochondria, 3-plasma membrane, 4-centriole, 5-neck d) 1-acrosome, 2-centriole, 3-mitochondria, 4-plasma membrane, 5-tail Ans. (b) 84. The actual genetic part of the sperm is: a) tail b) head c) acrosome d) middle piece Ans. (b) 85. Acrosome is found in the sperm at the: a) tail b) neck c) top of head d) middle piece Ans. (c) 86. Acrosome of sperm is formed from: a) Nucleus of spermatid b) Centrosome of spermatid c) Mitochondria of spermatid d) Golgi complex of spermatid Ans. (d) 87. The formation of the acrosome: a) involves mitotic activity b) occurs in the epididymis c) involves meiotic divisions d) involves the maturation of lytic enzymes Ans. (d) 88. The lytic enzyme released by sperm is: 6 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) ligase b) acrosome c) fertilizin d) hyaluronidase Ans. (d) 89. How many centrioles are normally present in a sperm? a) One b) Two c) Many d) None of these Ans. (b) 90. Which organelle is absent in human sperm? a) ER b) Nucleus c) Centriole d) Mitochondria Ans. (a) 91. Middle piece of sperm contains: a) mitochondria and Golgi body b) centriole and Golgi body c) axial filament and Golgi body d) mitochondria and axial filament Ans. (d) 92. Which of the following represents a condition where the motility of the sperms is highly reduced? a) Polyspermy b) Azoospermia c) Oilgospermia d) Asthenospermia Ans. (d) 93. During oogenesis, each diploid cell produces: a) Four functional cells b) Four nonfunctional polar bodies c) One functional egg and three polar bodies d) Two functional eggs and two polar bodies Ans. (c) 94. Oogonium is: a) haploid b) diploid c) triploid d) euploid Ans. (b) 95. The number of chromosomes in a mature gamete gets halved during: a) Meiosis II b) Formation of first polar body c) Formation of second polar body d) Division of secondary oocyte and secondary spermatocyte Ans. (b) 96. In which phase of cell division is oocyte arrested? a) Interphase b) Prophase I c) Anaphase II d) Both prophase I and II Ans. (b) 97. During oogenesis in mammals, the second meiotic division is completed a) Before ovulation b) After fertilization c) In the formation of the primary oocyte d) In the formation of the secondary oocyte Ans. (b) 98. How many eggs will be formed from 100 primary oocytes? a) 100 b) 200 c) 300 d) 400 Ans. (a) 99. How many ova and sperms will be produced from 100 secondary oocytes and 100 secondary spermatocytes during gametogenesis in man? a) 50 ova, 100 sperms b) 100 ova, 100 sperms c) 200 ova, 200 sperms d) 100 ova, 200 sperms Ans. (d) 100. 100 eggs and 100 sperms can be produced from ……. and ………meiotic divisions respectively. a) 25, 25 b) 100, 25 c) 100, 100 d) 25, 100 Ans. (b) 101. One million oocytes and one million secondary spermatocytes will give: a) 2 million ova 1 million sperms b) 2 million ova and 2 million sperms c) 1 million ova and 2 million sperms d) 1 million ova and 1 million sperms Ans. (c) 102. Which one of the following is haploid? a) Oogonia b) Primary oocyte c) Secondary oocyte d) Primary spermatocyte Ans. (c) 103. Which statement is true? a) At the onset of menopause, the human female stops producing FSH & LH b) Primary oocytes are produced by the human female throughout adolescence c) Oocytes produced by the females are stored in the seminiferous tubules d) At birth, the human female has produced all the oocytes she will ever produce Ans. (d) 104. Cytoplasm of ovum does not contain: a) Ribosomes b) Mitochondria c) Golgi bodies d) Centrosomes Ans. (d) 105. During a woman’s life time, she produces about: a) 40-50 eggs 7 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) b) 300 – 350 eggs c) 400 – 500 eggs d) 750 – 850 eggs Ans. (c) 106. The change in a mammalian sperm which prepares it to fertilize the ovum is termed: a) maturation b) preparation c) capacitation d) metamorphosis Ans. (c) 107. Capacitation of sperms occurs in: a) epididymus b) vas efferens c) vas deferens d) female genital tract Ans. (d) 108. During fertilization, the enzyme which facilitates penetration of the egg by the spermatozoan is: a) hyaluronidase b) acid phosphatase c) acetylcholinesterase d) alkaline phosphatase Ans. (a) 109. Match the following with correct combination: A hyaluronidase 1 acrosomal reaction B corpus luteum 2 morphogenetic movements 3 progesterone C gastrulation 4 mammary gland D capacitation 5 sperm activation E colostrum Answer codes: a) A = 5, B = 2, C = 4, D = 1, E = 3 b) A = 1, B = 3, C = 2, D = 5, E = 4 c) A = 3, B = 2, C = 5, D = 4, E = 1 d) A = 1, B = 2, C = 3, D = 4, E = 5 Ans. (b) 110. Find out the correct sequence in embryonic development of animal: a) Cleavage, zygote, fertilization, morula, blastula, gastrula b) Fertilization, zygote, cleavage, morula, blastula, gastrula c) Fertilization, cleavage, morula, zygote, blastula, gastrula d) Fertilization, zygote, blastula, morula, cleavage, gastrula Ans. (b) 111. What is true about cleavage in fertilized egg in humans? a) It is meroblastic b) It is identical to normal mitosis c) It starts when the egg reaches uterus d) It starts while the egg is in Fallopian tube Ans. (d) 112. Cleavage in mammals is: a) Discoidal b) Superficial c) Equal holoblastic d) Unequal holoblastic Ans. (d) 113. The embryo at 16-celled stage is known as: a) morula b) gastrula c) blastula d) blastomere Ans. (a) 114. Zone pellucida disintegrates a) just after fertilization b) before fertilization c) before cleavage d) after completion of cleavage Ans. (d) 115. Which germ layer develops first during embryonic development? a) ectoderm b) mesoderm c) endoderm d) both (b) and (c) Ans. (c) 116. In mammals, the body of embryo is formed from: a) trophoblast b) inner cell mass c) outer cell mass d) trophoectoderm Ans. (b) 117. The main function of trophoectoderm in mammalian embryo is: a) Formation of future ectoderm b) Protection of developing cells c) Drawing food for developing cells d) Formation of body of developing embryo Ans. (c) 118. Secretion of which of the following structure prepares inner wall of uterus for implantation? a) Gastrula b) Pituitary gland c) Corpus luteum d) Ovarian follicle Ans. (c) 119. In human, secretion of which of the following is used to confirm implantation of embryo? a) Corpus luteum b) Morula c) Trophoblast d) Inner cell mass Ans. (c) 120. The fertilized egg in human female is implanted in the uterus after: a) one month of fertilization b) two months of fertilization c) three weeks of fertilization d) about seven days of fertilization 8 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) Ans. (d) 121. What is implanted in the uterus? a) Morula b) Neurula c) Zygote d) Blastocyst Ans. (d) 122. The portion of the endometrium that covers the embryo and is located between the embryo and uterine cavity is the : a) decidua basalis b) decidua umbilicus c) decidua capsularis d) decidua functionalis Ans. (c) 123. Human embryo will be called as a ‘foetus’ after: a) two months b) six months c) four months d) seven months Ans. (a) 124. Gestation period is the duration: a) Of fertilization b) Between egg growth and ovulation c) Between fertilization and parturition d) Of preparation of sex cells and fertilization Ans. (c) 125. Study the following: A. Testosterone influences the male secondary sexual characters B. Gestation period in dog is approximately 276 days C. Bulbo-urethral glands secrete a cervical lubricant D. Placenta secretes estrogen The correct answer is: a) C and D b) A and B c) A and D d) B, C and D Ans. (c) Hint: Gestation period of dog is about 63 days. Bulbo urethral glands secrete a lubricant for vestibule. 126. The immediate cause of induction of ovulation in female is the large plasma surge of: a) LH b) FSH c) Estradiol d) Progesterone Ans. (a) 127. Correctly matched pairs are: 1. Clitoris - Erectile body in female homologous to penis of male 2. Sexual intercourse – coitus 3. Colostrum - Secretion found in seminal fluid 4. Areola - Pigmented circular area around the nipple Answer codes: a) 1 and 2 are correct b) 2 and 4 are correct c) 1 and 3 are correct d) 1, 2 and 4 are correct Ans. (d) 128. In oogenesis, haploid egg is fertilized by sperm at which stage? a) Ovum b) Oogonium c) Primary oocyte d) Secondary oocyte Ans. (d) 129. 2n = 6 in a primary spermatocyte which is in metaphase of first meiotic division. What shall be the total number of chromatids in each of the secondary spermatocyte? a) 6 b) 8 c) 24 d) 32 Ans. (a) 130. Some important events in the human female reproductive cycle are given below. Arrange the events in a proper sequence: A – Secretion of FSH, B – growth of corpus luteum, C-growth of the follicle and oogenesis, D-ovulation, E-sudden increase in the levels of LH a) ADCEB b) BACDE c) ACEDB d) CADBE Ans. (c) 131. The 16 cells stage of the human embryo is: a) smaller than the fertilized egg b) same size as the fertilized egg c) two times of the size of the fertilized egg d) four times the size of the fertilized egg Ans. (b) 132. The main function of the fimbriae of the Fallopian tube in females is to: a) help in the development of ovary b) help in the development of corpus luteum c) release to ovum from the Graafian follicle d) help in the collection of the ovum after ovulation Ans. (d) 133. The principal tail piece of human sperm shows the microtubular arrangement of: a) 7 + 2 b) 9 + 2 c) 11 + 2 d) 13 + 2 Ans. (b) 134. Eggs of placental mammals are expected to be a) alecithal b) polylecithal c) telolecithal d) mesolecithal Ans. (a) 9 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) 135. The eggs of some mammals have more yolk. They are: a) eutherians b) prototherians c) metatherians d) aquatic mammals Ans. (b) 136. Human egg is: a) alecithal b) centrolecithal c) telolecithal d) megalecithal Ans. (a) 137. Eggs having yolk in centre and cytoplasm in a peripheral region are called: a) isolecithal b) telolecithal c) microlecithal d) centrolecithal Ans. (d) 138. Which of the following is a primary egg membrane? a) Zona pellucida b) Corona radiata c) Shell d) All of these Ans. (a) 139. The sperm penetrates the ovum mainly: a) chemically b) thermally c) mechanically d) electrostatically Ans. (a) 140. What is true about fertilization? a) Only one sperm enters an egg b) Only acrosome of sperm enters the egg c) Entry of sperm activates the egg to complete mitosis d) Two haploid nuclei fuse but the fusion nucleus divides immediately to form two haploid nuclei Ans. (a) 141. Fertilization involves all of the following except: a) Metabolic activation of egg b) Breakdown of the acrosomal membrane c) Second meiotic division of sperm nucleus d) Binding of the sperm cell to coating surrounding the egg Ans. (c) 142. Which chemical of the egg attracts and holds sperm? a) Fertilizin b) Agglutinin c) Antifertilizin d) Antiagglutinin Ans. (a) 143. The chemical substance found in the surface layer of cytoplasm of spermatozoa is: a) agglutinin b) fertilizin c) hyaluronidase d) antifertilizin Ans. (d) 144. After a sperm has penetrated an ovum, entry of further sperm is prevented by: a) condensation of yolk b) formation of pigment coat c) development of vitelline membrane d) development of cortical reaction Ans. (d) 145. Secondary oocyte is formed: a) after fertilization b) before fertilization c) after complete meiosis of germ cells d) before puberty Ans. (b) 146. The fusion of male and female pronuclei is known as: a) eumixis b) capacitation c) acrosome reaction d) amphimixis Ans. (d) 147. The significance of fertilization: a) restore chromosome number b) double chromosome number c) reduce chromosome number d) none of the above Ans. (a) 148. Cleavage differs from mitosis in that it: a) occurs in zygote b) occurs in all body cells c) occurs only in invertebrates d) results in identical daughter cells Ans. (a) 149. Select the correct statement: a) Cleavage follows gastrulation b) Yolk sac of human embryo is rich in yolk. c) Cleavage is repeated equational divisions of zygote d) Gastrulation and blastulation are followed by each other Ans. (c) 150. Cleavage is a unique form of mitotic cell division in that: a) there is no growth of cells b) the nucleus does not particulars c) no spindle develops to drag chromosomes d) the plasma membranes of daughter cells do not separate Ans. (a) 151. Cleavage differs from mitosis in lacking: a) Synthetic phase b) Growth phase c) Both synthetic and growth phase d) Reduction in chromosome number Ans. (b) 152. During cleavage, the cell division is very rapid. The daughter cells do not undergo any growth and the cells thus become gradually smaller in volume. Hence: 10 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) b) c) d) the embryo becomes haploid the embryo grows in volume the embryo becomes smaller in volume there is no increase in the volume of the embryo Ans. (d) 153. Which one of the following is incorrect? a) fertilization follows capacitation b) cleavage of fertilized ovum results in blastula c) fusion of sperm and ovum occurs in fallopian tube d) cleavage leads to increase in the mass of protoplasm Ans. (d) 154. In embryo, cleavage brings about: a) increased size b) increased DNA content c) change in shape and size d) increased mass of protoplasm And. (b) 155. In an egg, the type of cleavage is determined by: a) number of egg membranes b) size and location of nucleus c) shape and size of the sperm d) amount and distribution of yolk Ans. (d) 156. When the cleavage furrow passes through the centre of animal-vegetal axis, the cleavage is: a) vertical b) latitudinal c) equatorial d) meridional Ans. (d) 157. A zygote is completely divided into two by a cleavage furrow. The cleavage type is: a) radial b) equatorial c) holoblastic d) meroblastic Ans. (c) 158. Solid ball of cells formed during cleavage is: a) morula b) foetus c) gastrula d) blastocyst Ans. (a) 159. A morula can be differentiated from blastula in: a) Absence of yolk b) Presence of cavity c) Absence of cavity d) Presence of more yolk Ans. (c) 160. The morphogenetic movements change the hollow spherical blastula into a: a) morula b) gastrula c) foetus d) embryonic disc Ans. (b) 161. The best definition of the process of gastrulation is that it is a process where the: a) Blastocoel is formed b) Zygote gets converted to larva c) Cells move to occupy their definite position d) Simple layered blastula becomes twolayered Ans. (c) 162. Which of the following tissues originate from the ectoderm of the embryo? a) Nervous tissue b) Epithelial tissue c) Muscular tissue d) Connective tissue Ans. (a) 163. During embryonic development, endoskeleton and muscles develop from: a) ectoderm b) mesoderm c) endoderm d) yolk plug Ans. (b) 164. Notochord develops from embryonic: a) ectoderm b) endoderm c) mesoderm d) all of these Ans. (c) 165. Which of the following sets contain only mesodermal structures? a) Liver, heart, blood, muscles b) Pancreas, heart, blood, bones c) Notochord, bones, cardiac muscles, blood d) Liver, blood, muscles, notochord Ans. (c) 166. Organs of which set are endodermal derivatives? a) Liver, thyroid, pancreas b) Brain, choroid, nerves c) Kidneys, ureters, ovary d) Testis, adrenal cortex, thymus Ans. (a) 167. The extraembryonic membranes of mammalian embryo are derived from: a) trophoblast b) follicle cells c) endodermal cells d) inner cell mass Ans. (a) 168. Which statement about trophoblast cells is true? a) They are endodermal cells b) They secrete proteolytic enzymes c) They are capable of producing dizygotic twins d) They are derived from the endoderm Ans. (b) 169. Mammalian foetus is directly surrounded by: 11 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) yolk sac cavity b) amniotic cavity c) allantoic cavity d) Primary digestive cavity Ans. (b) 170. The fluid released from the vagina just prior to childbirth is: a) amniotic fluid b) baby’s accumulated urine c) mother’s plasma from umbilical cord d) baby’s plasma form its foetal circulation Ans. (a) 171. What is the function of amniotic cavity? a) Nutrition b) Excretion c) Respiration d) Protection from shocks Ans. (d) 172. The function of allantoic-chorion in mammals is: a) excretory alone b) respiratory alone c) endocrine only d) excretory, respiratory and nutritive Ans. (d) 173. Placenta is universally present in: a) Birds b) Reptiles c) Eutherian mammals d) Prototherian mammals Ans. (c) 174. Placenta is: a) A cord that connects the foetus with wall of mother’s uterus b) A part of foetus only through which exchange of materials takes place between foetus and mother c) A part of mother’s uterine wall through which exchange of materials occur between mother and foetus d) Chorionic villi of foetus and a part of mother’s uterine wall through which chemical exchange between foetus and mother occurs Ans. (d) 175. Blood flowing through umbilical cord of mammalian embryo is: a) 100% foetal b) 100% maternal c) 50% maternal and 50% foetal d) 75% maternal and 25% foetal Ans. (a) 176. Structure connecting the foetus to placenta is: a) chorion b) amnion c) yolk sac d) umbilical cord Ans. (d) 177. Umbilical cord contains: a) placenta b) embryonic villi c) umbilicus d) umbilical artery and vein Ans. (d) 178. As a result of metabolism in mammalian embryo : a) No wastes are produced b) Wastes are absorbed by embryo c) Wastes are eliminated through mother’s body d) Accumulated wastes are eliminated after birth Ans. (c) 179. In human being, placenta is formed by: a) chorion b) amnion c) yolk sac d) all of these Ans. (a) 180. Mammalian placenta has minute finger-like projections known as; a) chorionic villi b) chorionic vessel c) chorionic extension d) chorionic network Ans. (a) 181. On the basis of nature of maternal and foetal tissue involved, types of placenta are: 1. haemo-endothelial placenta 2. haemo-chorial placenta 3. discoidal placenta 4. deciduate placenta Answer codes: a) 1 and 2 are correct b) 2 and 4 are correct c) 1 and 3 are correct d) 1,2 and 3 are correct Ans. (a) 182. Human placenta is: a) haemo-chorial b) epithelio –chorial c) haemo-endothelial d) syndesmo-chorial Ans. (a) 183. In simplest type of placenta, six barriers separates maternal blood from foetal blood. How many barriers are lost in human placenta? a) One b) Four c) Two d) Three Ans. (d) Hint: Uterine epithelium, uterine connective tissue & endothelium of maternal blood vessel disappear. 12 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) 184. Drugs that cause malformation in embryo during pregnancy are called : a) nicotine b) sedatives c) teratogens d) tranquillizer Ans. (c) 185. The chemical substance released by activated spermatozoa that acts on the ground substances of the follicle cells is known as: (Kerala PMT 2009) a) relaxin b) teratogen c) progesterone d) hyaluronidase Ans. (d) 186. Choose the incorrect statement from the following: a) In birds and mammals internal fertilisation takes place b) Colostrum contains antibodies and nutrients c) Polyspermy in mammals is prevented by the chemical changes in the sperm surface d) In the human female implantation occurs almost seven days after fertilisation Ans. (c) 187. Identify the correct statement from the following: a) High levels of estrogen triggers the ovulatory surge b) Oogonial cells start to proliferate and give rise to functional ova in regular cycles from puberty onwards. c) Sperms released from seminiferous tubules are highly motile d) Progesterone level is high during the post ovulatory phase of menstrual cycle Ans. (d) Hint: If in statement (a) it was mentioned ‘Pre-ovulatory surge of LH’ then it would also have been correct. 188. Spot the odd one out from the following structures with reference to the male reproductive system: a) Rete testis b) Epididymis c) Vasa efferentia d) Isthmus Ans. (d) 189. Seminal plasma, the fluid part of semen, is contributed by i. Seminal vesicle ii. Prostate iii. Urethra iv. Bulbourethral gland a) i and ii b) i, ii and iv c) ii, iii and iv d) i and iv Ans. (b) 190. Spermiation is the process of the release of sperms from: a) Seminiferous tubules b) Vas deferens c) Epididymis d) Prostate gland Ans. (a) 191. Mature Graafian follicle is generally present in the ovary of a healthy human female around a) 5 – 8 day of menstrual cycle b) 11 – 17 day of menstrual cycle c) 18 – 23 day of menstrual cycle d) 24 – 28 day of menstrual cycle Ans. (b) 192. Acrosomal reaction of the sperm occurs due to: a) Its contact with zona pellucida of the ova b) Reactions within the uterine environment of the female c) Reactions within the epididymal environment of the male d) Androgens produced in the uterus Ans. (a) 193. The immature male germ cell undergoes division to produce sperms by the process of spermatogenesis. Choose the correct one with reference to above. a) Spermatogonia have 46 chromosomes and always undergo meiotic cell division b) Primary spermatocytes divide by mitotic cell division c) Secondary spermatocytes have 23 chromosomes and undergo second meiotic division d) Spermatozoa are transformed into spermatids Ans. (c) 194. Match between the following representing parts of the sperm and their functions and choose the correct option. Col. A Col. B A. Head i. Enzymes B. Middle piece ii. Sperm motility C. Acrosome iii. Energy D. Tail iv. Genetic material Options: a) A-ii, B-iv, C-i, D-iii b) A-iv, B-iii, C-i, D-ii c) A-iv, B-i, C-ii, D-iii d) A-ii, B-i, C-iii, D-iv Ans. (b) 195. Which among the following has 23 chromosomes? a) Spermatogonia b) Zygote c) Secondary oocyte d) Oogonia Ans. (c) 196. Match the following and choose the correct options: A. Trophoblast (i) B. Cleavage (ii) Embedding of blastocyst in the endometrium Group of cells that would differentiate as embryo 13 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) C. Inner cell mass (iii) D. Implantation (iv) Outer layer of blastocyst attached to the endometrium Mitotic division of zygote a) A – (ii), B – (i), C – (iii), D – (iv) b) A – (iii), B – (iv), C – (ii), D – (i) c) A – (iii), B – (iv), C – (ii), D – (i) d) A – (ii), B – (iv), C – (iii), D – (i) Ans. (b) 197. Which of the following hormones is not secreted by human placenta? a) hCG b) Estrogens c) Progesterone d) LH Ans. (d) 198. The vas deferens receives duct from the seminal vesicle and opens into urethra as: a) Epididymis b) Ejaculatory duct c) Efferent ductule d) Ureter Ans. (b) 199. Urethral meatus refers to the: a) Urinogenital duct b) Opening of vas deferens into urethra c) External opening of the Urinogenital duct d) Muscles surrounding the urinogenial duct Ans. (c) 200. Morula is a developmental stage: a) Between the zygote and blastocyst b) Between the blastocyst and gastrula c) After the implantation d) Between implantation and parturition Ans. (a) 201. The cellular cover of the ovum at ovulation is: a) Corona radiata b) Zona radiata c) Zona pellucida d) Chorion Ans. (a) Hint: The human ovum is enclosed by two additional egg coats. Inner noncellular zona pellucida which is secreted by the ovum and is made of glycoproteins. It is a primary egg membrane. The second coat is the outer corona radiata, which is formed by the follicle cells of the ovary and is a secondary membrane. 202. Identify the odd one from the following: a) Labia minora b) Fimbriae c) Infundibulum d) Isthmus Ans. (a) 203. Consider the following statements regarding corpus luteum and corpus albicans associated with the ovary in mammals (i) Corpus luteum produces hormones for the ovulation (ii) Corpus luteum produces hormone which is essential for the preparation of reproductive tract for pregnancy and in many mammals for the maintenance of pregnancy. (iii) Following the degeneration of corpus luteum all that remains is whitish scarlike remnant connective tissue, the corpus albicans. (iv) Corpus albicans produces hormones for ovulation. Of these statement: a) (i) and (iii) are correct b) (ii) and (iii) are correct c) (ii) and (iv) are correct d) (iii) and (iv) are correct Ans. (b) 204. Which of the following statements about the female reproductive system are true or false? 1. Both FSH and LH are necessary for ovulation to take place. 2. Oestrogen tends to inhibit the production of FSH by the anterior pituitary gland. 3. Fertilization of the ovum by the spermatozoon normally takes place in the uterus. 4. Progesterone production is largely under the control of LH 5. Throughout the part of the menstrual cycle that follows ovulation, there is a slight rise in body temperature. a) + + - + + b) - - + + + c) - + - + d) + + - - Ans. (a) 205. Go through the following statements: (i) The transitional phase in females during which the genital organs regress in response to the withdrawl of gonadal activity is called climacteric. (ii) Menstrual blood is predominantly arterial and clots very fast due to the high content of fibrinogen in it. (iii) In pseudoprecocious puberty, the levels of sex hormones and gonadotropins are much higher than the normal levels. (iv) The primary oocyte starts its first meiotic division before birth but remains suspended in diplotene till puberty. Which of these are correct? a) (ii) & (iv) b) (i) & (iv) c) (i), (ii) & (iv) d) All are correct Ans. (b) 14 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) Hint: Menstrual blood normally does not clot due to the presence of fibrinolysin in it. In pseudo-precocious puberty, levels of gonadotropins are low. 206. Go through the following statements: (i) The secondary oocyte undergoes meiosis II which proceeds only till metaphase until a sperm enters it. (ii) Ovulation occurs about 36 – 38 hours after the start of LH surge at midcycle. (iii) In humans, it takes about 74 hours to form a mature sperm from a primitive germ cells. (iv) About 70% of the human ejaculate is contributed by bulbourethral glands Which of these are correct? a) (i) & (iii) b) (ii) & (iii) c) (i) & (ii) d) All are correct Ans. (c) Hint: It takes about 74 days for spermatogenesis. 70% of human ejaculate is contributed by seminal vesicle. 207. What would happen if vasa deferentia of man are cut? a) Sperms are non-nucleate b) Spermatogenesis does not occur c) Semen is without sperms d) Sperms are nonmotile Ans. (c) 208. Go through the following statements: (i) Relaxin produced by the ovary, facilitates delivery of the foetus by softening the connective tissue of pubic symphysis and relaxing the pelvic ligaments and joints. (ii) By the end of fifth month of pregnancy, the foetus develops limbs and digits. (iii) Thalidomide is a teratogenic drug which causes a condition called phocomelia. (iv) Although the levels of prolactin are high during pregnancy, milk secretion does not occur because of the high oestrogen and progesterone levels which make the breast unresponsive to the prolactin. Which of these are correct? a) (i), (ii) & (iii) b) (i), (iii) & (iv) c) (ii), (iii) & (iv) d) All are correct Ans. (b) Hint: Foetus develops limbs and digits by the end of second month. 209. The ________cells provide nutrition to male germ cells. The ____cells synthesise and secrete androgens Find the option which correctly fills in the above blanks in order a) Spermatogonia, Interstitial cells b) Interstitial cells; Spermatogonia c) Sertoli; Leydig d) Leydig; Sertoli Ans. (c) 210. In the given diagram; choose the option which correctly shows the match of the organ and the event Organ Event a) A Endometrium Secrete estrogen b) B Ovary Implantation c) C Isthmus Fertilization* Cervix Copulation d) D Ans. (c) 211. Identify X and Y in the diagram related to human reproductive system. Choose the correct option: Y – Epididymis Y – Seminal vesicle c) X- Prostate Y – Vasdeferens d) X- Bulbourethral gland Y- Seminal vesicle Ans. (b) 212. Three cells are labelled A, B and C. Select the option which correctly tells the cells which produce androgen. a) X- Seminal vesicle b) X- Prostate 15 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) Only A b) Only B c) A and C d) All three Ans. (a) 213. Given is the stage of a growing embryo and different regions of the fallopian tube marked 1, 2, 3, 4 Where do you think the given stage of embryo will be seen in the fallopian tube a) 4 b) 3 c) 2 d) 1 Ans. (a) 214. Find the correct match regarding human foetal development Month of pregnancy Event occurring a) End of 4th month Eyelashes appear rd b) End of 3 month Movements of Foetus c) End of 5th month Hair on head nd d) End of 2 month Organ systems develop Ans. (c) Hint: End of 2nd month = Foetal limbs and digits appear End of 3rd month = Major organ systems develop. Limbs well developed. External genitalia well developed. During 5th month = 1st movement Hair on the head appear End of 6th month = Eye lids separate Eye lashes appear 215. Consider the following statements 1. Oxytocin is a ‘milk ejection’ hormone 2. Progesterone causes termination of pregnancy 3. Relaxin causes termination of pregnancy Which of the statements given above is/are correct? a) 1 only b) 2 and 3 c) 3 only d) 1, 2 and 3 Ans. (a) 216. Consider the following statements. Placenta present in mammals acts as an endocrine tissue and produces 1. Human chorionic gonadotrophin 2. Oestrogen 3. Progesterone 4. Testosterone Which of these statements are correct? a) 1 and 4 b) 1 and 2 c) 1, 2 and 3 d) 2, 3 and 4 Ans. (c) 217. Consider the following 1. Endothelium of foetal blood capillaries 2. Connective tissue surrounding foetal blood capillaries 3. Chorionic epithelium 4. Maternal epithelium 5. Connective tissue surrounding maternal blood capillaries 6. Endothelium of maternal blood capillaries In the case of humans, the placenta comprises which of the above? a) 1, 2, 3, 4, 5 and 6 b) 1, 2, 3 and 6 c) 1, 2 and 3 d) 1, 2, 3 and 5 Ans. (c) 218. How are mature human sperm and ova similar? a) They are formed before birth b) They each have a flagellum that provides motility c) They are produced from puberty until death d) None of the above Ans. (d) 219. Trace a sperm cell from the structure where it is produced to fertilization of the egg: 1. Seminiferous tubules 2. Vas deferens 3. Uterus 4. Fallopian tube 5. Vagina 6. Epididymis 7. Urethra a) 6, 1, 2, 7, 5, 3, 4 b) 1, 6, 2, 7, 5, 3, 4 c) 1, 6, 2, 7, 5, 4, 3 d) 1, 2, 6, 7, 5, 3, 4 Ans. (b) 220. How are the time of ovulation and the onset of menstruation related in the human menstrual cycle? 16 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) Both are triggered by high luteinizing hormone “spikes” (sharp increase in concentration) b) Ovulation occurs approximately 7 days after the first day of menstruation c) Ovulation occurs approximately 14 days before the first day of menstruation d) All of the above Ans. (c) 221. Tick the correct statement a) Proximal and distal centrioles in the middle piece of sperm help anchor the flagellum b) Whereas proximal centriole is non functional, distal centriole acts as basal body for the flagellum of sperm c) The functions of proximal and distal centrioles are not known d) Proximal centriole forms the spindle fibres during cleavage and the distal centriole anchors the flagellum of sperm Ans. (d) 222. The intra-testicular genital duct system does not involvea) Rete testis b) Ductuli efference c) Tubuli recti d) Ductus deference Ans. (d) 223. Though, the total number of follicles in two ovaries of a normal young woman is about 4,00,000 the duration between menarche and menopause is limited. This is attributed to the – a) Follicular atresia b) Liquor folliculi c) Follicular proliferation d) Follicular plasticity Ans. (a) 224. Hypothalamus X Adenohypophysis Y Leydig cells Z Sertoli cells Testosterone Inhibin In the above diagram identify X, Y and Z with the sequence of number of appropriate hormones given below. (i) Progesteron (ii) LH (iii) HCG (iv) Estradiol (v) FSH (vi) GnRH a) (iii), (iv), (ii) b) (vi), (ii), (v) c) (i), (iv), (vi) d) (vi), (v), (ii) Ans. (b) 225. Which of the following hormones is not secreted by human placenta? a) Relaxin b) Lactogen c) Gonadotropin d) Oxytocin Ans. (d) 226. In humans, the first polar body formed during oogenesis has (i) 46 chromosomes (ii) 23 chromosomes (iii) 46 chromatids (iv) 23 chromatids a) (ii) and (iv) b) (ii) and (iii) c) (i) and (iii) d) (i) and (iv) Ans. (b) 227. Go through the following statements: (i) Androgens are produced by the interstitial cells (ii) Sertoli cells give rise to germ cells (iii) Secretions of male accessory glands constitute the seminal plasma which is rich in fructose, calcium and certain enzymes (iv) The presence or absence of hymen is a very reliable indicator of virginity. Which of these are correct? a) (i) & (iii) b) (iii) & (iv) c) (i), (iii) & (iv) d) All are correct Ans. (a) 228. Go through the following statements: (i) Primary spermatocytes undergo mitotic divisions to produce secondary spermatocytes (ii) Sperms released from the seminiferous tubules are fully mature and motile (iii) The head of sperm possesses many mitochondria which produce energy for the movement of tail (iv) The human male ejaculates about 20 – 30 million sperms during a coitus Which of these are correct? a) (i), (ii) & (iii) b) (ii), (iii) & (iv) c) (i), (iii) & (iv) d) All are wrong Ans. (d) Hint: Primary spermatocytes undergo first meiotic division to produce secondary spermatocyte. Sperms become full motile & mature in accessory ducts. Mitochondria are present in the middle piece of sperm. Single ejaculate contain 200 – 300 million sperms. 229. Go through the following statements (i) Mammary glands are modified sweat glands and each mammary gland consists of 15–25 lobules of the compound tubuloalveolar type. (ii) The tertiary follicle is characterised by a fluid filled cavity called antrum 17 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) (iii) Both LH and FSH attain a peak level towards the middle of the menstrual cycle (iv) In oogenesis, both first and second meiotic divisions are unequal Which of these are correct? a) (ii) & (iii) b) (i), (iii) & (iv) c) (i), (ii) & (iv) d) All are correct Ans. (d) 230. Go through the following statements: (i) The fluid in the antrum of follicle is called liquor amnii (ii) During follicular atresia, some thecal cells persist and secrete a small amount of androgen (iii) Vagina is devoid of glands (iv) Bartholin’s glands of females correspond to the Cowper’s glands of the male and their ducts open just outside the hymen into the vestibule. Which of these are correct? a) (i), (ii) & (iii) b) (ii), (iii) & (iv) c) (i), (iii) & (iv) d) All are correct Ans. (b) Hint: Fluid in antrum of follicle is called liquor folliculi. 231. Go through the following statements: (i) In both pre-pubertal and post-menopausal females, there are low levels of female sex hormones and high levels of gonadotrophins. (ii) There is no bleeding in an oestrous cycle as the broken endometrium is absorbed. (iii) Oestrogen is mainly secreted by the granulosa cells and progesterone mainly by the theca cells (iv) Some of the menopausal symptoms can be reversed HRT wherein a small dose of gonadotrophins is given to the patient. Which of these are correct? a) (ii) & (iii) b) (i), (ii) & (iv) c) (i), (ii) & (iii) d) All are correct Ans. (a) 232. Go through the following statements: (i) HCG from placenta stimulates the sertoli cells of the male foetus to produce testosterone and is thus indirectly involved in the development of male external genitalia (ii) Sertoli cells secrete a protein called inhibin, which suppresses FSH synthesis. (iii) Humans have haemo-endothelial type of placenta (iv) Oxytocin stimulates the placenta to secrete prostaglandins which in turn stimulate more contractions of uterus. Which of these are correct? a) (i) & (iv) b) (ii) & (iv) c) (i), (ii) & (iv) d) All are correct Ans. (b) Hint: HCG stimulates Leydig cells to secrete testosterone. Human placenta is haemo-chorial. 233. Match list-I (cell type) with list-II (characteristic) and select the correct answer using the codes given below the lists List-I List-II A. Spermatogonium 1. Does not divide. B. Spermatocyte 2. Divides mitotically C. Spermatid 3. Divides meiotically D. Sertoli cell 4. Divides both mitotically and meiotically 5. Nourishes other cell types Codes: A B C D a) 5 3 1 4 b) 1 3 4 5 c) 3 2 4 1 d) 2 3 1 5 Ans. (d) 234. Go through the following statements: (i) Spermatids are haploid cells derived from secondary spermatocytes as a result of second meiotic division (ii) LH acts on Leydig cells and stimulates synthesis and secretion of androgens (iii) The spermatids are transformed into spermatozoa by the process of spermiation (iv) In females, oogonia are added only till the age of puberty. Which of these are correct? a) (i) & (ii) b) (i), (ii) & (iv) b) (ii), (iii), (iv) d) All are correct Ans. (a) Hint: Spermatids are transformed into spermatozoa (sperms) through spermiogenesis. Spermiation is the process of release of sperms from seminiferous tubules. Oogonia are not formed after birth. 235. Read the following statements carefully: (i) Lack of menstruation in female of reproductive age group (i.e., between puberty and menopause) is always indicative of pregnancy. 18 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) (ii) The mature Graffian follicle ruptures to release the ootid from the ovary by the process called ovulation (iii) Relaxin, hCG and hPL are produced in women only during pregnancy (iv) During pregnancy, levels of hormones like estrogens, progestogens, cortisol and thyroxine are increased several folds in the mother. Which of these are correct? a) (i) & (iii) (b) (i), (ii) & (iv) c) (iii) & (iv) d) All are correct Ans. (c) Hint: Graffian follicle ruptures to release secondary oocyte. 236. Both corpus luteum and macula lutea are: (AIIMS – 2003) a) Found in human ovaries b) A source of hormones c) Characterized by a yellow colour d) Contributory in maintaining pregnancy Ans. (c) 237. The phase of menstrual cycle in humans that lasts for 7-8 days, is: (AIIMS – 2003) a) Follicular phase b) Ovulatory phase c) Luteal phase d) Menstruation Ans. (a) 238. Which one of the following statements with regard to embryonic development in humans is correct? (AIIMS – 2003) a) Cleavage divisions bring about considerable increase in the mass of protoplasm. b) In the second cleavage division, one of the two blastomeres usually divides a little sooner than the second c) With more cleavage divisions, the resultant blastomeres become larger and larger d) Cleavage division results in a hollow ball of cells called morula Ans. (b) 239. Assertion: Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals. Reason: Eggs of most mammals, including humans, are of centrolecithal type. (AIIMS – 2003) a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion, then mark a. b) If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion, then mark b. c) If Assertion is true statement but Reason is false, then mark c. d) If both Assertion and Reason are false statements, then mark d. Ans. (c) 240. Which one of the following events is correctly matched with the time period in a normal menstrual cycle? (AIIMS – 2005) 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 Ans. (b) 241. Which of the following has the longest gestation period (AIIMS – 2010) a) Man b) Cat c) Dog d) Elephant Ans. (d) Hint: In cats and dogs it is about 63. In man 280 days and in elephant 624 days. 242. Go through the following diagram carefully: (AIIMS – 2010) Which of the following option shows the correct labelling and events occurring in that organ: a) (i) Ovary – Follicle rupture; Beginning of 1st and 2nd meiotic division (ii) Fallopian tube – Fertilisation; Completion of 2nd meiotic division (iii) Uterus – Blastocyst formation; Implantation b) (i) Ovary – Follicle rupture; Completion of 2nd meiotic division (ii) Fallopian tube – Fertilisation; Blastocyst formation (iii) Uterus - Implantation c) (i) Ovary – Follicle maturation; Beginning of 1st and 2nd meiotic division (ii) Fallopian tube – Fertilisation; Completion of 2nd meiotic division (iii) Uterus – Beginning of cleavage; Implantation d) (i) Ovary – Follicle maturation; Completion of 2nd meiotic division (ii) Fallopian tube – Beginning of cleavage; Implantation (iii) Uterus – Fertilisation; Blastocyst formation 19 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) Ans. (a) 243. Secretion of GnRH would lead to: (AIIMS – 2010) a) Secretion of testosterone leading to mammary gland development b) Release of prolactin leading to milk production in mammary glands c) Secretion of LH and FSH leading to follicle development d) All of the above Ans. (c) 244.Find the odd one out: (AIIMS – 2010) a) HIV b) Trichomoniasis c) Gonorrhoea d) Typhoid Ans. (d) Hint: (a), (b) and (c) are STDs. 245. Assertion: If scrotal sacs are removed, testosterone is still found in the body. Reason: Small amount of androgens is secreted by the adrenal cortex. (AIIMS – 2011) a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion, then mark a. b) If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion, then mark b. c) If Assertion is true statement but Reason is false, then mark c. d) If both Assertion and Reason are false statements, then mark d. Ans. (a) 246. The entry of additional sperms into the ovum is prevented because of: (AIIMS – 2011) a) Release of secretions from the acrosome b) Changes in the zona pellucida c) Changes in the corona radiata d) Contractions and secretions of the fallopian tube Ans. (b) 247. Ovulation in the human female normally takes place during the menstrual cycle (CBSE PRELIMS – 2004) a) At the beginning of the proliferative phase b) At the end of the proliferative phase c) At the mid secretory phase d) Just before the end of the secretory phase Ans. (b) 248. Sertoli cells are regulated by the pituitary hormone known as: (CBSE PRELIMS – 2006) a) FSH b) GH c) Prolactin d) LH Ans. (a) 249. Withdrawl of which of the following hormones is the immediate cause of menstruation? (CBSE PRELIMS – 2006) a) Estrogen b) FSH c) FSH-RH d) Progesterone Ans. (d) 250. Which part of ovary in mammals acts as an endocrine gland after ovulation (CBSE PRELIMS – 2007) a) Stroma b) Germinal epithelium c) Vitelline membrane d) Graffian follicle Ans. (d) 251. In the human female, menstruation can be deferred by the administration of: (CBSE PRELIMS – 2007) a) Combination of FSH and LH b) Combination of estrogen and progesterone c) FSH only d) LH only Ans. (b) 252. Compared to a bull a bullock is docile because of (CBSE PRELIMS – 2007) a) Higher levels of cortisone b) Lower levels of blood testosterone c) Lower levels of adrenalin/noradrenalin in its blood d) Higher levels of thyroxin Ans. (b) 253. In humans, at the end of the first meiotic division, the male germ cells differentiate into the: (CBSE PRELIMS – 2008) a) Spermatozonia b) Primary spermatocytes c) Secondary spermatocytes d) Spermatids Ans. (c) 254. Which extraembryonic membrane in humans prevents desiccation of the embryo inside the uterus? (CBSE PRELIMS – 2008) a) Amnion b) Chorion c) Allantois d) Yolk sac Ans. (a) 255. Which one of the following statements is incorrect about menstruation? (CBSE PRELIMS – 2008) a) The beginning of the cycle of menstruation is called menarche. b) During normal menstruation about 40 ml blood is lost. c) The menstrual fluid can easily clot. d) At menopause in the female, there is especially abrupt increase in gonadotropic hormones Ans. (c) 20 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) 256. In human adult females oxytocin: (CBSE PRELIMS – 2008) a) Causes strong uterine contractions during parturition b) Is secreted by anterior pituitary c) Stimulates growth of mammary glands d) Stimulates pituitary to secrete vasopressin Ans. (a) 257. Which one of the following is the correct matching of the events occurring during menstrual cycle? (CBSE PRELIMS – 2009) a) Development of corpus luteum b) Menstruation c) Ovulation d) Proliferative phase Secretory phase and increased secretion of progesterone. Breakdown of myometrium and ovum not fertilized. LH and FSH attain peak level and sharp fall in the secretion of progesterone. Rapid regeneration of myometrium and maturation of Graafian follicle. Ans. (a) 258. The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testis is: (CBSE PRELIMS – 2009) a) Spermatid-spermatocyte-spermatogoniasperms b) Spermatogonia-spermatid-spermatocytesperms c) Spermatocyte-spermatogonia-spermatidsperms d) Spermatogonia-spermatocyte-spermatidsperms Ans. (d) 259. Foetal ejection reflex in human female is induced by: (CBSE PRELIMS – 2009) a) Fully developed foetus and placenta b) Differentiation of mammary glands c) Pressure exerted by amniotic fluid d) Release of oxytocin from pituitary Ans. (a) 260. Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female? (CBSE PRELIMS – 2009) a) Maintenance of high concentration of sex-hormones in the blood stream b) Retention of well-developed corpus luteum c) Fertilisation of the ovum d) Maintenance of the hypertrophical endometrial lining Ans. (c) 261. 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: (CBSE PRELIMS – 2009) A B C a) Vas deferens b) Ureter Bulbourethrall gland Prostate c) Ureter Seminal vesicle Seminal vesicle Prostate d) Vas deferens Seminal vesicle Seminal vesicle Prostate D Prostate Bulbourethral gland Bulbourethral gland Bulbourethrall gland Ans. (d) 262. A change in the amount of yolk and its distribution in the egg will affect: (CBSE PRELIMS – 2009) a) Number of blastomeres produced b) Fertilization c) Formation of zygote d) Pattern of cleavage Ans. (d) 263. Seminal plasma in humans is rich in: (CBSE PRELIMS – 2009) a) Glucose and certain enzymes but has no calcium b) Fructose and certain enzymes but poor in calcium c) Fructose, calcium and certain enzymes d) Fructose and calcium but has no enzymes Ans. (c) Hint: Seminal plasma is the term used for semen. Calcium is present in prostatic secretion. 264. Vasa efferentia are the ductules leading from: (CBSE PRELIMS – 2010) a) Epididymis to urethra b) Testicular lobules to rete testis c) Rete testis to vas deferens d) Vas deferens to epididymis Ans. (c) Hint: The path followed by sperms is seminiferous tubules tubuli recti rete testis Vasa efferentia epididmis vas deferens ejaculatory duct urethra. 21 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) None of the above options is correct. The best option seems to be (c). 265. The first movements of the foetus and appearance of hair on its head are usually observed during which month of pregnancy? (CBSE PRELIMS – 2010) a) Third month b) Fourth month c) Fifth month d) Sixth month Ans. (c) 266. Which one of the following statements about human sperm is correct? (CBSE PRELIMS – 2010) a) Acrosome serves no particular function b) Acrosome has a conical pointed structure used for piercing and penetrating the egg resulting in fertilization c) The sperm lysins in the acrosome dissolve the egg envelope facilitating fertilization d) Acrosome serves as a sensory structure leading the sperm towards the ovum Ans. (c) 267. Seminal plasma in human males is rich in: (CBSE PRELIMS – 2010) a) Ribose and potassium b) Fructose and calcium c) Glucose and calcium d) DNA and testosterone Ans. (b) Hint: Fructose is mainly present in secretions of seminal vesicles and calcium in prostatic secretions. 268. Sertoli cells are found in: (CBSE PRELIMS – 2010) a) Pancreas and secrete cholecystokinin b) Ovaries and secrete progesterone c) Adrenal cortex and secrete adrenaline d) Seminiferous tubules and provide nutrition to germ cells Ans. (d) 269. The part of Fallopian tube closest to the ovary is: (CBSE PRELIMS – 2010) a) Ampulla b) Isthmus c) Infundibulum d) Cervix Ans. (c) 270. The signals for parturition originate from: (CBSE PRELIMS – 2010) a) Fully developed foetus only b) Placenta only c) Placenta as well as fully developed foetus d) Oxytocin released from maternal pituitary Ans. (c) 271. The second maturation division of the mammalian ovum occurs: (CBSE PRELIMS – 2010) a) In the Graafian follicle following the first maturation division b) Shortly after ovulation before the ovum makes entry into the Fallopian tube c) Until after the ovum has been penetrated by a sperm d) Until the nucleus of the sperm has fused with that of the ovum Ans. (c) 272. Which one of the following statements about morula in humans is correct? (CBSE PRELIMS – 2010) a) It has more cytoplasm and more DNA than an uncleaved zygote b) It has almost equal quantity of cytoplasm as an uncleaved zygote but much more DNA c) It has far less cytoplasm as well as less DNA than in an uncleaved zygote d) It has more or less equal quantity of cytoplasm and DNA as in uncleaved zygote Ans. (b) 273. If for some reason, the vasa efferentia in the human reproductive system get blocked, the gametes will not be transported from: (CBSE PRELIMS – 2011) a) Testes to epididymis b) Epididymis to vas deferens c) Ovary to uterus d) Vagina to uterus Ans. (a) 274. The testes in humans are situated outside the abdominal cavity inside a pouch called scrotum. The purpose served is for: (CBSE PRELIMS – 2011) 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 Ans. (a) 275. The figure given below depicts a diagrammatic sectional view of the female reproductive system of humans. Which one set of three parts out of I-VI have been correctly identified? (CBSE PRELIMS – 2011) 22 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) a) (II) Endometrium, (III) Infundibulum, (IV) Fimbriae b) (III) Infundibulum, (IV) Fimbriae, (V) Cervix c) (IV) Oviducal funnel, (V) Uterus, (VI) Cervix d) (I) Perimetrium, (II) Myometrium, (III) Fallopian tube Ans. (b) 276. What is correct to say about the hormone action in humans? (CBSE PRELIMS – 2012) a) Secretion of thymosins is stimulated with aging b) In females, FSH first binds with specific receptors on ovarian cell membrane c) FSH stimulates the secretion of estrogen and progesterone d) Glucagon is secreted by β-cells of Islets of Langerhans and stimulates glycogenolysis Ans. (b) 277. In a normal pregnant woman, the amount of total gonadotropin activity was assessed. (CBSE PRELIMS – 2012) The result expected was: a) High level of circulating HCG to stimulate endometrial thickening b) High levels of FSH and LH in uterus to stimulate endometrial thickening c) High level of circulating HCG to stimulate estrogen and progesterone synthesis d) High level of circulating FSH and LH in the uterus to stimulate implantation of the embryo Ans. (c) 278. Signals for parturition originate from (CBSE PRELIMS – 2012) a) Oxytocin released from maternal pituitary b) Placenta only c) Fully developed foetus only d) Both placenta as well as fully developed foetus Ans. (d) 279. The Leydig cells as found in the human body are the secretory source of: (CBSE PRELIMS – 2012) a) Intestinal mucus b) Glucagon c) Androgens d) Progesterone Ans. (c) 280. Which one of the following statements is false in respect of viability of mammalian sperm? (CBSE PRELIMS – 2012) a) Survival of sperm depends on the pH of the medium and is more active in alkaline medium b) Viability of sperm is determined by its motility c) Sperms must be concentrated in a thick suspension d) Sperm is viable for only up to 24 hours Ans. (d) 281. Signals from fully developed foetus and placenta ultimately lead to parturition which requires the release of (CBSE MAINS – 2010) a) Estrogen from placenta b) Oxytocin from maternal pituitary c) Oxytocin from foetal pituitary d) Relaxin from placenta Ans. (b) 282. In human female the blastocyst (CBSE MAINS – 2010) a) Forms placenta even before implantation b) Gets implanted into uterus 3 days after ovulation c) Gets nutrition from uterine endometrial secretion only after implantation d) Gets implanted in endometrium by the trophoblast cells Ans. (d) 283. Secretions from which one of the following are rich in fructose, calcium and some enzymes? (CBSE MAINS – 2010) a) Male accessory glands b) Liver c) Pancreas d) Salivary glands Ans. (a) 284. What happens during fertilisation in humans after many sperms reach close to the ovum? (CBSE MAINS – 2011) 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 Ans. (a) 23 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) 285. About which day in a normal human menstrual cycle does rapid secretion of LH (popularly called LH-surge) normally occurs? (CBSE MAINS – 2011) a) 14th day b) 20th day th c) 5 day d) 11th day Ans. (a) 286. The secretory phase in the human menstrual cycle is also called: (CBSE MAINS – 2012) a) Luteal phase and lasts for about 13 days b) Follicular phase and lasts for about 13 days c) Luteal phase and lasts for about 6 days d) Follicular phase and lasting for about 6 days Ans. (a) 287. Identify the human development stage shown below as well as the related right place of its occurrence in a normal pregnant woman, and select the right option for the two together. (CBSE MAINS – 2012) Options: Developmental stage a) Blastocyst b) 8-celled morula c) d) Late morula Blastula Site of occurrence Uterine wall Starting point of Fallopian tube Middle part of Fallopian tube End part of Fallopian tube Ans. (a) Hint: The embryo with 8-16 blastomeres is called a morula, and is present in the end part of fallopian tube. Morula forms the blastocyst as it reaches the uterine cavity and then blastocyst implants in the endometrium. Thus, the options (b), (c), (d) are all wrong. 288. Which hormone is detected in urine as pregnancy test? (CHD. CET – 2008) a) hCG b) Estrogen c) Progesterone d) Luteinising hormone Ans. (a) 289. Bartholin glands are situated (CHD. CET – 2008) a) On the sides of head of some amphibians b) At the reduced tail end of birds c) On either side of vagina in humans d) On either side of vas deferens in humans Ans. (c) 290. Placenta in human beings is formed by (CHD. CET – 2008) a) Amnion b) Chorion c) Allantois d) Chorion and Allantois Ans. (b) 291. The progesterone is secreted by: (CHD. CET – 2009) a) Graffian follicles b) Corpus luteum c) Interstitial cells d) Corpus albicans Ans. (b) 292. Testosterone, the male sex hormone is synthesized in the: (CHD. CET – 2009) a) Seminiferous tubules b) Interstitial cells c) Vas deferns d) Prostate gland Ans. (b) 293. Metadiscoidal placenta is found in: (CHD. CET – 2010) a) Pig b) Rabbit c) Humans d) Cow Ans. (c) Hint: Pig has diffused non-deciduous placenta. Cow has cotyledonary non-deciduous placenta. Rabbit has discoidal deciduous placenta. 294. Which gland secretes alkaline mucous in the urethra to neutralize the acidity of urine? (CHD. CET – 2011) a) Prostrate gland b) Cowper’s gland c) Seminal vesicles d) Preputial glands Ans. (b) 295. A temporary endocrine gland in humans is: (CHD. CET – 2012) a) Islets of Langerhans b) Pineal body c) Corpus Luteum d) Corpora allata Ans. (c) 296. Braxton Hicks contractions occur during: (CHD. CET – 2012) a) Passage of food through alimentary canal b) Peristaltic movements c) Pregnancy d) Lactation Ans. (c) 297. The correct sequence of human embryonic development is: (CHD. CET – 2012) a) Blastocoel – gastrocoel – neural crest – notochord b) Gastrocoel – blastocoel – notochord – neural crest c) Gastrocoel – blastocoel – neural crest – notochord 24 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) d) Blastocoel – neural crest – gastrocoel – notochord Ans. (a) 298. The onset of menstrual cycle in females of anthropoid primates is known as: (CHD. CET – 2012) a) Puberty b) Menarche c) Menopause d) Menstruation Ans. (b) 299. Thick yellow high protein fluid produced by the mammary glands of a woman during first 2-3 days after child birth is known as: (CHD. CET – 2012) a) Meconium b) Hymen c) Cumulus oophorous d) Colostrum Ans. (d) 300. Location and Secretions of Leydig cells are (H.P. PMT – 2010) a) Liver – Cholesterol b) Ovary – Estrogen c) Testis – Androgens d) Pancreas – Glucagon Ans. (c) 301. Which hormones are produced in women only during pregnancy? (H.P. PMT – 2010) a) human chorionic Gonadotropin (hcG) b) human placental Lactogen (hpL) c) Relaxin d) All the above Ans. (d) 302. The menstrual phase is followed by (H.P. PMT – 2010) a) Luteal phase b) Follicular phase c) Fertilization d) Implantation Ans. (b) 303. Which layer of uterus undergoes cyclical changes during menstrual cycle? (H.P. PMT – 2011) a) Perimetrium b) Myometrium c) Endometrium d) All the above Ans. (c) 304. Which type of Germ cells contains 23 chromosomes? (H.P. PMT – 2011) a) Spermatogonia b) Secondary spermatocytes c) Primary spermatocytes d) None of the above Ans. (b) 305. In human beings, Menstrual cycle ceases around 50 years of age that is termed as (H.P. PMT – 2011) a) Menarche b) Diapause c) Menopause d) None of the above Ans. (c) 306. Generally the first movement of the human foetus in the womb is noticed during (H.P. PMT – 2012) a) Ist month b) 3rd month th c) 5 month d) 8th month Ans. (c) 307. The hormone secreted by corpus luteum is (H. P. PMT – 2012) a) Luteinizing hormone b) Estrogen c) Follicle stimulating hormone d) Progesterone Ans. (d) 308. The internal cavity commonly formed by cell division prior to gastrulation is the (DUMET – 2010) a) Enteron b) Blastopore c) Blastocoel d) Coelom Ans. (c) 309. The number of autosomes in human primary spermatocyte is (DUMET – 2011) a) 46 b) 44 c) 23 d) 22 Ans. (b) 310. Which of the following organs is devoid of glands? (DUMET – 2011) a) Uterus b) Vagina c) Vulva d) Oviduct Ans. (b) 311. Primary spermatocyte differs from spermatogonium in (DUMET – 2011) a) Number of chromosomes b) Size and volume c) DNA content d) Size of chromosomes Ans. (b) Hint: Primary spermatocytes are about double the volume of spermatogonia as they formed as a result of growth phase. 312. In human, cleavage divisions are (DUMET – 2011) a) Slow and synchronous b) Fast and synchronous c) Slow and asynchronous d) Fast and asynchronous Ans. (c) 313. What is the correct sequence of sperm formation? (NEET – 2013) a) Spermatogonia, spermatozoa, spermatocyte, spermatid b) Spermatogonia, spermatocyte, spermatid, spermatozoa c) Spermatid, spermatocyte, spermatogonia. spermatozoa 25 DR. ARVIND’S BIOLOGY CLASSES (A UNIT OF MED-XEL TUTORIALS) d) Spermatogonia, spermatocyte, spermatozoa, spermatid Ans. (b) 314. Which one of the following is not the function of placenta? It: (NEET – 2013) a) Facilitates removal of carbon dioxide and waste material from embryo. b) Secretes oxytocin during parturition. c) Facilitates supply of oxygen and nutrients to embryo. d) Secretes estrogen. Ans. (b) 315. Product of sexual reproduction generally generates: (NEET – 2013) a) New genetic combination leading to variation b) Large biomass c) Longer viability of seeds d) Prolonged dormancy Ans. (a) 316. Menstrual flow occurs due to lack of: (NEET – 2013) a) Oxytocin b) Vasopressin c) Progesterone d) FSH Ans. (c)