Human reproduction, sex hormones and STIs

Learning objectives

Identify the parts of the male (testes, scrotum, sperm ducts, prostate gland, urethra and penis) and female (ovaries, oviducts, uterus, cervix and vagina) reproductive systems and state their functions, and describe fertilisation as the fusion of the nuclei of a sperm cell and an egg cell

Explain the adaptive features of sperm (flagellum, mitochondria and enzymes in the acrosome) and egg cells (energy stores and a jelly coat that changes after fertilisation)

Describe how the zygote forms an embryo that implants in the wall of the uterus, identify the umbilical cord, placenta, amniotic sac and amniotic fluid and state their functions, and at Extended describe the exchange of dissolved nutrients, gases and excretory products across the placenta and state that some toxins (for example nicotine) and pathogens (for example the rubella virus) can cross it

Describe the roles of testosterone and oestrogen in puberty and the changes in the ovaries and uterus lining during the menstrual cycle, and at Extended explain the control of the cycle and of pregnancy by FSH, LH, oestrogen and progesterone and where these hormones are produced

Compare male and female gametes in size, structure, motility and numbers

Describe sexually transmitted infections, state that HIV is a pathogen causing an STI that may lead to AIDS, describe how HIV is transmitted and explain how the spread of STIs is controlled