Human Reproduction

36 solved questions from Class 12 Biology, each with the full working. Tap any question to see the step-by-step solution.

• 1 What is the primary topic or theoretical principle explored in 'Human Reproduction' (Class 12 BIOLOGY)? medium MCQ Chapter Core Principle
• 2 Which key mechanism or analytical rule is highlighted in 'Human Reproduction'? medium MCQ Key Analytical Mechanism
• 3 What is the primary topic or principle explained in 'Human Reproduction' (Class 12 Biology)? medium MCQ Chapter Core Concept
• 4 Which key observation or fact is central to understanding 'Human Reproduction'? medium MCQ Key Fact & Mechanism
• 5 Why is the study of 'Human Reproduction' important for students of Class 12? medium MCQ Learning Significance
• 6 What is a common application or real-world example related to 'Human Reproduction'? medium MCQ Real World Application
• 7 What key takeaway should students retain after completing 'Human Reproduction'? medium MCQ Chapter Summary & Takeaway
• 8 Describe the hormonal regulation of the menstrual cycle, indicating the role of the hypothalamus, pituitary gland, ovary and the feedback mechanisms in both the follicular and luteal phases. hard 4 marks Hormonal control of menstrual cycle
• 9 How many mature sperm cells are produced from a single spermatogonium during spermatogenesis? medium 2 marks Outcome of spermatogenesis
• 10 During the luteal phase, serum progesterone rises from 2 ng/ml to 15 ng/ml. What is the fold increase in progesterone concentration? medium 2 marks Quantitative change in hormone level
• 11 How many secondary spermatocytes are produced from a single primary spermatocyte during meiosis I? easy 1 mark Meiosis I outcome
• 12 A fertilized egg divides into 8 cells after 18 hours. Assuming exponential division with no cell death, how many cells will be present after 30 hours? medium 3 marks Cell division timing
• 13 Explain the stages of fertilization from sperm binding to implantation, including the role of zona pellucida, cortical reaction, and formation of the blastocyst. hard 4 marks Fertilization and early embryonic development
• 14 During the follicular phase of the menstrual cycle, which sequence of hormonal events correctly leads to ovulation? medium MCQ 2 marks Hormonal cascade in follicular phase
• 15 During sperm capacitation in the female reproductive tract, which of the following changes occurs? easy MCQ 1 mark Sperm capacitation changes
• 16 Explain the formation of the blastocyst from a fertilized ovum, describing the roles of zona pellucida, cortical granule exocytosis, inner cell mass, and trophoblast. hard 5 marks Blastocyst formation and implantation
• 17 Describe the role of luteinizing hormone in the luteal phase of the menstrual cycle. medium 2 marks LH action in luteal phase
• 18 A woman undergoing IVF retrieved 15 mature oocytes, 12 fertilized into zygotes. If each zygote divides into 2 cells every 24 hours, how many cells will be present after 72 hours? Assume no cell death. hard 3 marks Cell division doubling time
• 19 Explain how progesterone produced by the corpus luteum modifies the endometrial lining to make it receptive for embryo implantation. Include the cellular and molecular changes involved. hard 3 marks Endometrial receptivity
• 20 Describe the complete process of implantation, from the arrival of the blastocyst in the uterine cavity to the formation of the placenta, highlighting the roles of the trophoblast, decidua, cytokines, and maternal blood vessels. hard 4 marks Placental formation
• 21 Which of the following best describes the sequence of hormonal events that leads to ovulation during the follicular phase? medium MCQ 2 marks Follicular hormonal sequence
• 22 During an IVF treatment, a technician retrieves 20 oocytes from a patient. If 14 of them are mature (metaphase II), what percentage of the retrieved oocytes were mature? easy 1 mark Maturation rate in IVF
• 23 During the luteal phase, which hormone is primarily responsible for maintaining the endometrial lining for potential implantation? medium MCQ 2 marks Progesterone role in luteal phase
• 24 State the role of the zona pellucida after a sperm has fused with the ovum. easy 1 mark Zona pellucida function post‑fertilization
• 25 In a laboratory study, 2,500 spermatogonia are induced to undergo complete spermatogenesis. Assuming each spermatogonium gives rise to one primary spermatocyte, each primary spermatocyte yields two secondary spermatocytes, each secondary spermatocyte forms two spermatids, and each spermatid differentiates into a mature spermatozoon, calculate the total number of mature spermatozoa produced. hard 3 marks Spermatogenesis yields four sperm per spermatogonium
• 26 During a laboratory experiment, 3,200 spermatogonia are induced to undergo complete spermatogenesis. Each spermatogonium gives rise to one primary spermatocyte; each primary spermatocyte yields two secondary spermatocytes; each secondary spermatocyte forms two spermatids; each spermatid differentiates into a mature spermatozoon. How many mature spermatozoa are produced? easy 2 marks Spermatogenesis cell multiplication
• 27 Which of the following sequences correctly represents the hormonal events that lead to ovulation during the follicular phase of the menstrual cycle? medium MCQ 3 marks Hormonal regulation of ovulation
• 28 Explain the complete process of implantation, from the arrival of the blastocyst in the uterine cavity to the formation of the placenta, highlighting the roles of the trophoblast, decidua, cytokines, and maternal blood vessels. hard 5 marks Implantation and placental formation
• 29 Describe how progesterone produced by the corpus luteum modifies the endometrial lining to prepare it for possible implantation. medium 4 marks Progesterone action in endometrium
• 30 During an IVF treatment, a technician retrieves 20 oocytes from a patient. If 14 of them are mature (metaphase II), what percentage of the retrieved oocytes were mature? medium 2 marks Percentage calculation in IVF
• 31 Which hormone is primarily responsible for maintaining the endometrial lining during the luteal phase of the menstrual cycle? easy MCQ 1 mark Luteal phase hormonal maintenance
• 32 State the role of the zona pellucida after a sperm has fused with the ovum. hard 3 marks Zona pellucida post‑fertilization block
• 33 Describe the complete process of implantation, from the arrival of the blastocyst in the uterine cavity to the formation of the placenta, highlighting the roles of the trophoblast, decidua, cytokines, and maternal blood vessels. hard 5 marks Implantation and placental development
• 34 Which of the following changes takes place during sperm capacitation in the female reproductive tract? medium MCQ 2 marks Sperm capacitation process
• 35 If 12 mature oocytes are fertilized during an IVF cycle, and 70 % of them develop into 2‑cell embryos by 24 hours, how many 2‑cell embryos are present? easy 1 mark Percentage of embryos developing
• 36 During spermatogenesis, 4,500 spermatogonia are induced. Each spermatogonium gives rise to one primary spermatocyte; each primary produces two secondary spermatocytes; each secondary forms two spermatids; each spermatid differentiates into a mature spermatozoon. How many mature spermatozoa are produced? hard 3 marks Spermatogenesis yield