BIOM*3200 Unit 7 (Reproduction)

beepboop

1. What is the process by which germ cells (sperm and ova) are formed, involving a reduction in chromosome number? a. Mitosis b. Fertilisation c. Meiosis d. Differentiation

c

2. Which of the following is the term for a fertilised ovum? a. Gamete b. Morula c. Zygote d. Blastocyst

c

3. How many chromosomes does each gamete receive in humans? a. 46 b. 23 c. 22 d. 1

b

4. What are the first 22 pairs of chromosomes called in humans? a. Sex chromosomes b. Homologous chromosomes c. Autosomal chromosomes d. Haploid chromosomes

c

5. What is the chromosomal composition of a female human? a. XY b. XX c. XO d. YY

b

6. What is the chromosomal composition of a male human? a. XX b. XY c. XO d. YY

b

7. Which chromosome contains the SRY gene, crucial for the development of testes? a. X chromosome b. Y chromosome c. Autosomal chromosome 1 d. Autosomal chromosome 23

b

8. What are Wolffian ducts destined to develop into in a male embryo? a. Uterine tubes b. Vagina c. Epididymis and vas deferens d. Ovaries

c

9. What are Müllerian ducts destined to develop into in a female embryo? a. Testes b. Epididymis c. Uterus and uterine tubes d. Prostate gland

c

10. What hormone causes the regression of Müllerian ducts in male embryonic development? a. Testosterone b. Dihydrotestosterone (DHT) c. Anti-Müllerian hormone (AMH) d. Oestrogen

c

11. What is genomic imprinting? a. A process where genes are lost during differentiation. b. A process where both parental alleles are always expressed. c. A process where either the maternal or paternal allele of certain genes is silenced. d. A process where DNA base sequences are altered due to environmental factors.

c

12. Which enzyme converts testosterone into dihydrotestosterone (DHT) in target cells? a. Aromatase b. 5α-reductase c. Kinase d. Hydrolase

b

13. What syndrome results from the presence of an extra X chromosome (XXY genotype) in a male? a. Turner's syndrome b. Testicular feminisation syndrome c. Klinefelter's syndrome d. Congenital adrenal hyperplasia

c

14. What concept explains that epigenetic changes can be passed from a parent's gametes to an offspring? a. Genetic recombination b. Genomic imprinting c. Epigenetic inheritance d. Gene conversion

c

15. What hormone is secreted in a pulsatile fashion by the hypothalamus to regulate FSH and LH secretion? a. Testosterone b. Oestrogen c. Gonadotropin-releasing hormone (GnRH) d. Prolactin

c

16. Why is pulsatile secretion of GnRH and gonadotropins important? a. To increase continuous high hormone levels. b. To prevent desensitisation and downregulation of target glands. c. To directly stimulate spermatogenesis. d. To inhibit the secretion of growth hormone.

b

17. Which neuropeptide family provides essential excitatory input to GnRH-releasing neurons? a. Endorphins b. Kisspeptins c. Enkephalins d. Somatostatin

b

18. Which hormone, secreted from white adipose tissue, is believed to promote the onset of puberty by stimulating GnRH production? a. Ghrelin b. Leptin c. Adiponectin d. Resistin

b

19. What is the average age of menarche (first menstruation) in girls in the general population? a. Age 10 b. Age 12.6 c. Age 14 d. Age 15

b

20. Which gland is believed to secrete melatonin, a hormone potentially involved in regulating human reproduction and circadian rhythms? a. Pituitary gland b. Adrenal gland c. Pineal gland d. Thyroid gland

c

21. What term describes the increased muscle tone observed during the excitation phase of the human sexual response? a. Vasocongestion b. Myotonia c. Ejaculation d. Orgasm

b

22. What is the engorgement of a sexual organ with blood called during sexual arousal? a. Myotonia b. Orgasm c. Vasocongestion d. Ejaculation

c

23. Which cells in the testes are the targets of LH action and secrete testosterone? a. Sertoli cells b. Spermatogonia c. Interstitial endocrine (Leydig) cells d. Germ cells

c

24. Which cells in the seminiferous tubules are the targets of FSH action and support spermatogenesis? a. Leydig cells b. Spermatocytes c. Spermatids d. Sertoli cells

d

25. What is the primary function of testosterone in males after puberty? a. Inhibiting bone growth b. Stimulating female secondary sex characteristics c. Promoting spermatogenesis and development of male secondary sex characteristics d. Lowering blood glucose levels

c

26. Which male accessory sex organ contributes the most to the volume of semen, secreting a fluid rich in fructose? a. Prostate gland b. Bulbourethral glands c. Epididymis d. Seminal vesicles

d

27. What is the process by which spermatids are transformed into spermatozoa? a. Spermatogenesis b. Meiosis c. Spermiogenesis d. Mitosis

c

28. What structure helps make the seminiferous tubules an immunologically privileged site by producing FAS ligand? a. Leydig cells b. Spermatocytes c. Sertoli cells d. Epididymis

c

29. What is the typical daily sperm production in the seminiferous tubules of a man? a. 1 million b. 10 million c. 100 million d. At least 300 million

d

30. What is the cap-like enzyme-filled vesicle on the head of a sperm cell called, crucial for fertilisation? a. Nucleus b. Mitochondrion c. Acrosome d. Flagellum

c

31. Which gas neurotransmitter is critical for mediating erection of the penis? a. Nitrous oxide (N2O) b. Carbon dioxide (CO2) c. Nitric oxide (NO) d. Carbon monoxide (CO)

c

32. What is the minimum sperm count per millilitre of ejaculate for a male to be considered fertile? a. 5 million b. 10 million c. 20 million d. 60 million

c

33. Which structures, extensions of the uterine tubes, partially cover each ovary and help draw released ova into the tubes? a. Fimbriae b. Villi c. Microvilli d. Cilia

a

34. At what stage of meiosis is a secondary oocyte arrested when it is ovulated? a. Prophase I b. Metaphase I c. Prophase II d. Metaphase II

d

35. Which ovarian follicle stage contains a single, fluid-filled cavity called an antrum? a. Primordial follicle b. Primary follicle c. Secondary follicle d. Graafian (mature) follicle

d

36. What is the thin transparent layer of protein and polysaccharides that surrounds the secondary oocyte? a. Corona radiata b. Granulosa cells c. Zona pellucida d. Theca interna

c

37. Which hormone surge triggers ovulation? a. FSH b. Oestradiol c. Progesterone d. LH

d

38. What structure forms in the ovary after ovulation from the ruptured follicle and secretes progesterone and oestradiol? a. Graafian follicle b. Corpus albicans c. Corpus luteum d. Primary follicle

c

39. How many mature ova does a woman usually ovulate per month? a. Two b. Five c. One d. Zero

c

40. What is the first day of menstruation typically considered in the menstrual cycle? a. Day 7 b. Day 14 c. Day 1 d. Day 28

c

41. What characterises the follicular phase of the menstrual cycle in terms of ovarian changes? a. Formation of the corpus luteum. b. Growth of ovarian follicles and secretion of oestradiol. c. Regression of the corpus luteum. d. Ovulation.

b

42. What hormone is primarily responsible for the rapid rise in basal body temperature observed after ovulation? a. Oestradiol b. FSH c. LH d. Progesterone

d

43. What describes the changes in the endometrium during the proliferative phase of the menstrual cycle? a. Sloughing off of the functional layer. b. Growth and proliferation of endometrial cells due to oestradiol. c. Secretion of glycogen and glycoproteins. d. Ischemic necrosis.

b

44. Which hormone, produced by the corpus luteum, is responsible for stimulating the development of uterine glands and secretions in the secretory phase? a. Oestradiol b. FSH c. Progesterone d. LH

c

45. What happens to FSH and LH secretion at the end of the luteal phase if fertilisation does not occur? a. Both increase due to positive feedback. b. Both decrease due to high oestradiol and progesterone. c. FSH decreases, LH increases. d. Both increase due to reduced negative feedback.

d

46. How do oral contraceptive pills primarily prevent pregnancy? a. By increasing GnRH secretion. b. By causing continuous high levels of FSH and LH. c. By inhibiting gonadotropin secretion and preventing ovulation. d. By stimulating implantation.

c

47. What is the term for the cessation of ovarian function and menstruation, usually occurring around age 50? a. Puberty b. Menarche c. Menopause d. Amenorrhea

c

48. Where does fertilisation normally occur in humans? a. Ovary b. Uterus c. Uterine tube d. Vagina

c

49. What is the process by which sperm become capable of fertilising ova in the female reproductive tract? a. Acrosome reaction b. Capacitation c. Spermiogenesis d. Ovulation

b

50. What is triggered when sperm binds to specific carbohydrates in the zona pellucida, leading to the release of acrosomal enzymes? a. Cortical reaction b. Fertilisation cone formation c. Acrosome reaction d. Pronuclear fusion

c

51. What is the rapid spread of a Ca2+ wave across the oocyte cytoplasm after sperm fusion, which prevents polyspermy? a. Acrosome reaction b. Cortical reaction c. Zona reaction d. Fertilisation potential

b

52. Which structure, provided by the sperm to the zygote, is needed for the organisation of microtubules into the spindle apparatus for mitosis? a. Mitochondria b. Nucleus c. Centrosome d. Acrosome

c

53. From which parent is all of the mitochondrial DNA in most people inherited? a. Father b. Mother c. Both parents equally d. It is newly generated

b

54. What is the hollow structure formed by cleavage that consists of an inner cell mass and a surrounding trophoblast? a. Morula b. Zygote c. Gastrula d. Blastocyst

d

55. Which hormone, secreted by the trophoblast cells of the blastocyst, maintains the mother's corpus luteum for the first 10 weeks of pregnancy? a. LH b. FSH c. Human chorionic gonadotropin (hCG) d. Prolactin

c

56. What is the term for the process where the blastocyst attaches to and penetrates the uterine wall? a. Ovulation b. Cleavage c. Implantation d. Gastrulation

c

57. Which fetal component forms the primary villi that contribute to the placenta? a. Amnion b. Yolk sac c. Chorion frondosum d. Allantois

c

58. Which maternal tissue component contributes to the placenta? a. Myometrium b. Endometrium (decidua basalis) c. Perimetrium d. Broad ligament

b

59. How many cell layers typically separate maternal blood from fetal blood within the placenta? a. One b. Two c. Three d. Four

b

60. What is the primary method of exchange for oxygen, nutrients, and wastes between fetal and maternal blood in the placenta? a. Active transport b. Facilitated diffusion c. Simple diffusion d. Bulk transport

c

61. Which hormone, secreted by the placenta, has actions similar to prolactin and growth hormone, promoting breast development and protein synthesis? a. hCG b. Progesterone c. Human chorionic somatomammotropin (hCS) d. Oestradiol

c

62. What are the two main agents that stimulate uterine contractions during parturition (childbirth)? a. Oestrogen and relaxin b. Oxytocin and prostaglandins c. Prolactin and hCS d. Adrenaline and noradrenaline

b

63. What is the first milk produced after birth, rich in antibodies and immune components? a. Whole milk b. Colostrum c. Transition milk d. Mature milk

b

64. Which hormone stimulates the contraction of mammary glands and ducts during the milk-ejection reflex? a. Prolactin b. Oestrogen c. Oxytocin d. Progesterone

c

65. What type of immunity is provided to a baby by maternal antibodies in breast milk? a. Active immunity b. Passive immunity c. Cell-mediated immunity d. Innate immunity

b

66. What prenatal diagnostic procedure involves withdrawing amniotic fluid for examination of fetal cells? a. Chorionic villus sampling (CVS) b. Amniocentesis c. Ultrasound d. Maternal blood DNA analysis

b

67. What term describes cells that are relatively undifferentiated and able to divide and produce different specialized cells? a. Gametes b. Somatic cells c. Stem cells d. Differentiated cells

c

68. What is the term for a cell (like the zygote) that can produce all tissue types and form an entire new organism when appropriately stimulated? a. Pluripotent b. Multipotent c. Totipotent d. Unipotent

c

69. What kind of stem cells can form the three embryonic germ layers but cannot contribute to the extraembryonic membranes (placenta)? a. Totipotent stem cells b. Multipotent stem cells c. Pluripotent stem cells d. Unipotent stem cells

c

70. What is the technique where the nucleus from a differentiated somatic cell is transferred to the cytoplasm of an enucleated ovum to produce stem cell lines? a. In vitro fertilisation b. Somatic cell nuclear transfer c. Genetic recombination d. CRISPR-Cas9 system

b

71. What is the difference between therapeutic cloning and reproductive cloning? a. Therapeutic cloning aims to create a new organism, while reproductive cloning aims to produce stem cell lines for disease treatment. b. Therapeutic cloning produces embryonic stem cells for disease treatment, while reproductive cloning aims to create a new organism. c. Therapeutic cloning uses adult stem cells, while reproductive cloning uses embryonic stem cells. d. Therapeutic cloning is legal everywhere, while reproductive cloning is illegal everywhere.

b

72. Which type of stem cells are found in protected locations in the adult body where renewal of specialised cells is required, such as neural stem cells in the hippocampus? a. Embryonic stem cells b. Pluripotent stem cells c. Totipotent stem cells d. Adult stem cells

d

73. What are induced pluripotent stem cells (iPS cells) derived from? a. Embryonic inner cell mass b. Somatic cell nuclear transfer c. Differentiated fibroblasts treated with specific regulatory molecules d. Gametes

c

74. What is one concern about using pluripotent stem cells for regenerative medicine, mentioned in the sources? a. They are too difficult to obtain. b. They cannot differentiate into all cell types. c. They can proliferate like tumour cells. d. They are immunologically rejected by the patient.

c

75. What happens to the chromosomes during the first meiotic division? a. Duplicate chromatids are separated into daughter cells. b. Homologous chromosomes line up side by side and are separated into two daughter cells. c. The chromosome number remains the same as the parent cell. d. All chromosomes are replicated.

b

76. Which of the following is true regarding crossing-over? a. It occurs during metaphase II of meiosis. b. It involves the exchange of parts of homologous chromosomes at prophase I. c. It results in identical gametes. d. It only occurs in male meiosis.

b

77. What is the significance of genetic recombination resulting from meiosis? a. It ensures that all gametes are identical. b. It reduces the chromosome number from 46 to 23. c. It provides additional genetic diversity for sexually reproducing organisms. d. It only affects the sex chromosomes.

c

78. What term refers to the diploid parent cell that undergoes meiosis in the testes to produce sperm? a. Spermatid b. Spermatogonium c. Secondary spermatocyte d. Spermatozoon

b

79. How many haploid spermatids are produced from one primary spermatocyte at the end of meiosis? a. One b. Two c. Three d. Four

d

80. What type of protein replaces histone proteins in DNA during spermiogenesis, inducing great compaction of chromatin? a. Actin b. Myosin c. Protamines d. Tubulin

c

81. What is the term for the process where germ cells (sperm and ova) are formed within the gonads? a. Mitosis b. Differentiation c. Meiosis d. Fertilisation

c

82. Which of the following statements about sex chromosomes is true? a. Females have one X and one Y chromosome. b. The X and Y chromosomes contain the same genes. c. Males have two X chromosomes. d. The X chromosome has significantly more genes than the Y chromosome.

d

83. What is the fate of the "unstuck" daughter cell that differentiates and migrates upward in stratified epithelia after mitosis of basal cells? a. It remains attached to the basement membrane. b. It undergoes further mitosis to renew the basal cell population. c. It replaces cells lost from the top layer. d. It becomes a connective tissue cell.

c

84. What is the condition caused by excessive alcohol consumption during pregnancy, which can damage the corpus callosum and basal nuclei in the brain? a. Down's syndrome b. Fetal alcohol syndrome c. Klinefelter's syndrome d. Tay-Sach's disease

b

85. What is the main reason why sexual reproduction offers an advantage for species survival over evolutionary time? a. It ensures all offspring are identical to the parents. b. It produces genetically unique individuals through random gene combinations. c. It prevents any genetic mutations from occurring. d. It speeds up the reproductive cycle.

b

86. During which trimester of pregnancy do the ovaries mature in a female fetus? a. First trimester b. Second trimester c. Third trimester d. After birth

c

87. Which phase of the human sexual response is characterised by myotonia and vasocongestion? a. Resolution b. Orgasm c. Plateau d. Excitation

d

88. What term describes the fact that the two parental alleles of about 200 known genes are expressed differently, often with one being silenced? a. Allelic variation b. Genetic drift c. Genomic imprinting d. Gene silencing

c

89. What is the primary role of the corpus luteum in the non-fertile luteal phase? a. To stimulate ovulation. b. To secrete high levels of FSH and LH. c. To secrete progesterone and oestradiol, preparing the uterus for potential implantation. d. To inhibit the growth of new follicles.

c

90. When a secondary oocyte is fertilised, what is the immediate event that occurs concerning its meiotic division? a. It arrests at metaphase II. b. It completes the first meiotic division. c. It completes the second meiotic division. d. It immediately undergoes mitosis.

c

91. What embryonic structure implants into the mother's uterus around the 6th day following fertilisation? a. Morula b. Zygote c. Blastocyst d. Gastrula

c

92. What type of cloning involves creating a new organism from a somatic cell, rather than producing stem cell lines? a. Therapeutic cloning b. Reproductive cloning c. Induced pluripotent cloning d. Gene cloning

b

93. What is the approximate weight of the uterus at term during pregnancy? a. 60g b. 250g c. 500g d. 1kg

d

94. What effect does testosterone secretion in the male fetus have during the second trimester of pregnancy? a. It increases, leading to continuous masculinisation. b. It declines, making the gonads of both sexes relatively inactive at birth. c. It remains constant. d. It stimulates oestrogen production.

b

95. What is the name of the two distinct myocardia found in the heart? a. Atria and ventricles b. Left and right ventricles c. Atria and atrioventricular nodes d. Sinoatrial node and Purkinje fibres

a

96. What does the phrase "fight or flight" aptly summarise? a. The parasympathetic system. b. The sympathetic system. c. The somatic nervous system. d. The central nervous system.

b

97. What hormone is secreted by the anterior pituitary that stimulates the adrenal cortex? a. Growth hormone (GH) b. Thyroid-stimulating hormone (TSH) c. Adrenocorticotropic hormone (ACTH) d. Follicle-stimulating hormone (FSH)

c

98. In the context of cancer, what provides immunological surveillance mainly through cytotoxic T lymphocytes and natural killer cells? a. Antibodies b. Macrophages c. The immune system d. Complement system

c

99. What is the term for the formation of spermatozoa, including meiosis and maturational processes in the seminiferous tubules? a. Oogenesis b. Gametogenesis c. Spermatogenesis d. Spermiogenesis

c

100. What is the typical life span of an erythrocyte in the blood? a. 12 hours to 3 days b. 10 to 30 days c. Approximately 120 days d. 300 days

c