Reproduction, Embryology, and Development

• What is a method of asexual reproduction in Hydra?

  Budding
• What is parthenogenesis?

  Mother generates eggs into haploid embryos
• What is fragmentation in asexual reproduction?

  Splitting into identical copies
• What is binary fission?


  A method of asexual reproduction
• What are the pros of asexual reproduction?

  • Faster reproduction without mating
  • Rapid population increase
  • Independent offspring production
  • Genetically identical offspring
  • Quick colonisation of habitats
  • Energy saved from not producing gametes
  • Direct transmission of favourable traits
• What are the cons of asexual reproduction?

  • Reduced genetic diversity
  • Limited adaptability to changes
  • Accumulation of harmful mutations
  • Lack of resilience to environmental changes
  • Limited evolutionary changes
  • Inbreeding depression
  • Survival depends on specific conditions
• How does asexual reproduction compare to sexual reproduction?

  Asexual is faster but less adaptable
• What are the stages of mammalian sexual reproduction?

  1. Gametes
  2. Fertilization
  3. Zygote
  4. Embryo
  5. Foetus
  6. Birth
  7. Neonate
  8. Infant
  9. Child
  10. Adolescent
  11. Adult
• What is the role of gametes in sexual reproduction?

  They mix genetic information from two individuals
• What processes are involved in gamete production?

  • Oogenesis in females
  • Spermatogenesis in males
• What do ovaries produce?

  Oocytes
• What happens during ovulation?

  Mature oocyte leaves the ovary
• What is the role of fimbriae in reproduction?


  They receive the mature oocyte
• What is the endometrium's role during pregnancy?

  It is where the embryo implants
• What are oogonia?

  They are the 'seed bank' in ovaries
• How many oogonia are present before birth?

  2 million
• What happens to oogonia after birth?

  They expand by mitosis
• What triggers the resumption of Meiosis I in oocytes?

  High levels of luteinizing hormone (LH)
• What is the outcome of the first meiotic division in oocytes?

  Production of a polar body and secondary oocyte
• What happens to the secondary oocyte if fertilisation occurs?

  It completes the second meiotic division
• What is the role of the kinetochore in meiosis?

  It attaches microtubules for chromosome segregation
• What can result from improper segregation of sister chromatids?

  Miscarriages or birth defects
• What is the hypothalamic-pituitary-ovary (HPO) axis?

  • Involves hypothalamus and anterior pituitary gland
  • Releases GnRH, FSH, and LH
  • Regulates female reproductive hormones
• What does GnRH stimulate in the anterior pituitary gland?

  Release of FSH and LH
• What is the role of inhibin in the reproductive system?

  Forms a negative feedback loop with FSH
• What happens when oestrogen levels are low?

  Decreases GnRH, FSH, and LH production
• What occurs when oestrogen levels are high?

  Forms a positive feedback loop with GnRH
• What is the role of theca and granulosa cells in oestrogen production?

  They convert cholesterol into progesterone and androgens
• What happens to androstenedione in the granulosa cells?

  It is converted into oestrone and oestradiol
• What are the phases of the menstrual cycle?

  1. Follicular phase
  2. Ovulatory phase
  3. Luteal phase
  4. Menstruation
• What triggers ovulation during the menstrual cycle?

  High levels of LH from oestrogen increase
• What is the corpus luteum's function?

  Secretes progesterone and oestrogen
• How long does the corpus luteum remain active after ovulation?


  14 days
• What occurs during the proliferative phase of the menstrual cycle?


  Rising oestrogen levels stimulate uterine changes
• What are the effects of oestrogen during the proliferative phase?

  Stimulates growth of fallopian tubes and endometrium
• What happens during the secretory phase of the menstrual cycle?


  Both oestrogen and progesterone are present
• What is the role of the placenta during pregnancy?

  Supplies nutrients and removes waste
• What is the function of chorionic villi in the placenta?

  Facilitates nutrient and waste exchange
• What hormonal changes occur during pregnancy?

  Increased oestrogen and progesterone levels
• What can result from gametes with anomalous chromosome numbers?

  Genetic defects and pregnancy loss