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• Male reproductive system:

  • Testes: produce sperm cells and testosterone
  • Epididymis: storage for sperm cells until ejaculation
  • Scrotum: protects the testes, maintains a cooler temperature for sperm development
  • Vas deferens/sperm duct: transports sperm from epididymis to urethra
  • Seminal vesicle and prostate gland: produce seminal fluid for sperm survival and neutralizing vaginal acidity
• Urethra carries semen from sperm duct to penis tip and urine out of the body; if urethra diameter reduces, it can cause pain and difficulty in urination and ejaculation, and increase the risk of bladder infection
• Female reproductive system:

  • Ovary: produces egg cells and estrogen
  • Oviduct: site of fertilization, moves egg/zygote to uterus
  • Uterus: implantation of embryo, site of fetal growth
  • Cervix: closes during pregnancy, dilates at birth
  • Vagina: site of copulation, sperm deposition, and birth canal
• Menstrual cycle:

  • Involves changes in uterus lining and ovary
  • Hormones involved: Oestrogen, Progesterone, FSH, LH
  • FSH stimulates follicle development and egg maturation
  • LH stimulates ovulation and release of egg into oviduct
  • Progesterone maintains uterus lining for implantation
• How to calculate the fertile period:

  • Ovulation occurs around day 14 of a 28-day cycle
  • Sperm survive for about 3 days, egg for about 2 days
  • Fertile period is around days 12 to 16 of the cycle
• Placenta:

  • Organ connecting fetus to uterine wall for nutrient exchange
  • Umbilical cord: connects placenta to fetus, carries blood, oxygen, and nutrients
  • Fertilization: fusion of male and female nuclei
  • Menstruation: drop in estrogen and progesterone levels, repair of uterus lining
• The placenta is an organ that connects the developing fetus to the uterine wall, responsible for the exchange of nutrients, gases, and waste products between the mother and the fetus

  
• The umbilical cord is a tube that connects the placenta to the fetus, carrying blood, oxygen, and nutrients to the fetus, and removing waste products
• During the menstrual cycle, ovulation is stimulated by LH, leading to the release of the egg from the ovary into the oviduct
• Fertilization occurs by the fusion of male and female nuclei in the oviduct, forming a zygote that divides by mitosis to form an embryo
• Implantation of the embryo in the uterus lining occurs, followed by placenta formation to allow the exchange of materials with the fetus
• The placenta has finger-like projections (chorionic villi) to provide a large surface area for the exchange of substances between the mother and the fetus
• The placenta acts as a barrier, reducing the risk of passage of pathogens from mother to fetus, preventing mixing of different blood groups, and protecting delicate blood vessels of the fetus from the mother's high blood pressure
• The placenta secretes progesterone in the last 6 months of pregnancy to maintain the thickness of the uterus lining and prevent uterine contraction
• The umbilical cord joins the fetus with the placenta, containing blood vessels (arteries and veins) to transport CO2 and urea from the fetus to the mother, and oxygen and nutrients (glucose) from the mother to the fetus
• The amniotic sac secretes amniotic fluid, allowing the fetus to practice movement, acting as a mechanical shock absorber, preventing temperature fluctuations, and providing a sterile environment for the fetus
• Infertility treatment options include using FSH and LH, infertility drugs, IVF (in vitro fertilization), and artificial insemination
• IVF involves collecting egg and sperm cells, allowing external fertilization, developing the zygote into an embryo, and inserting multiple embryos into the uterus, with implications such as high cost and potential for multiple births
• Artificial insemination involves collecting sperm cells from a donor, inserting them near the time of ovulation in the cervix, and is socially accepted if the donor is the husband
• Sexually transmitted diseases like HIV weaken the immune system by destroying T lymphocytes, leading to less stimulation of other lymphocytes and phagocytes, making the body prone to infections
• HIV is transmitted through unprotected sexual intercourse, sharing contaminated needles, blood transfusion, mother to fetus during birth or through breast feeding
• Part 1 reproduction


  21/2/2024
• Menstrual cycle


  Changes in uterus lining and ovary
• Male reproductive system


  • Testes: produce sperm cells and testosterone
  • Epididymis: storage of sperm cells till ejaculation
  • Scrotum: protect testes, maintain cooler temperature for sperm development
  • Vas deferens/sperm duct: transport sperm cells to urethra
  • Seminal vesicle and prostate gland: produce seminal fluid for sperm survival, swimming, and neutralizing vaginal acidity
• Urethra


  Carries semen from sperm duct to tip of the penis and urine out of the body
• If there is a reduction in diameter of urethra
• Effects of reduction in diameter of urethra


  • Pain and difficulty in urination and ejaculation
  • Increase risk of bladder infection
• Female reproductive system


  • Ovary: production of egg cell and oestrogen
  • Oviduct: site of fertilisation, movement of egg/zygote to uterus
  • Uterus: implantation of embryo, growth and development into fetus
  • Cervix: closes during pregnancy, dilates at birth
  • Vagina: site of copulation, sperm deposition, and birth canal
• Puberty


  • Male: testosterone released from testes
  • Female: oestrogen released from the ovary
• Responsible for the development of secondary sexual characteristics
• Common changes in boys and girls during puberty
• Menstrual cycle


  Involves changes in uterus lining and ovary, influenced by Oestrogen, Progesterone, FSH, LH, and FELP to stimulate various releases
• Growth spurt

  Sudden faster rate of growth, body smells increase
• Menstrual cycle


  Cycle that lasts for 28 days involving changes in Uterus lining and Ovary
• Hormones involved in the menstrual cycle

  • Oestrogen
  • Progesterone
  • FSH
  • LH
  • FELP
• FSH


  Stimulate the development of follicle to allow maturation of an egg, Stimulate release of oestrogen
• Oestrogen

  Build up uterus lining to be ready for implantation, Stimulate the release of LH, Inhibit the release of FSH
• LH


  Stimulate the release of the egg from ovary into the oviduct to be ready for fertilisation, Stimulate release of progesterone
• Progesterone


  Maintain the thickness of uterus lining to be ready for implantation, Inhibit the release of LH and FSH
• Site of hormone production

  • Pituitary gland
  • Ovary