1. 1
   A textbook diagram labels the parts of the male reproductive system: testes, scrotum, sperm ducts, prostate gland, urethra and penis, alongside a diagram of the female reproductive system showing ovaries, oviducts, uterus, cervix and vagina.

   (a)

   A textbook diagram of the male reproductive system labels the site where sperm cells are produced. Which structure produces sperm?

   [1 mark]

   • AThe prostate gland
   • BThe testes
   • CThe sperm duct
   • DThe urethra

   (b)

   In the female reproductive system diagram, fertilisation normally takes place in the tube connecting the ovary to the uterus. What is this tube called?

   [1 mark]

   • AThe cervix
   • BThe vagina
   • CThe oviduct
   • DThe urethra

   (c)

   State the function of the scrotum in the male reproductive system and the function of the uterus in the female reproductive system.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A biologist compares a human sperm cell and an egg cell under a microscope, noting that the sperm is much smaller with a flagellum and many mitochondria, while the egg cell is much larger with energy stores and a jelly coat, and only one sperm normally fertilises the egg.

   (a)

   What is the function of the many mitochondria packed near the base of the sperm cell's tail?

   [1 mark]

   • ATo provide energy from respiration for the movement of the tail
   • BTo store nutrients for the developing embryo
   • CTo produce the jelly coat that changes at fertilisation
   • DTo carry the genetic information of the egg cell

   (b)

   Only one sperm cell normally fertilises the egg cell, even though millions of sperm may be released. Which adaptive feature of the egg cell helps to prevent more than one sperm from entering it?

   [1 mark]

   • AThe flagellum
   • BThe acrosome enzymes
   • CThe large number of mitochondria
   • DThe jelly coat, which changes structure after the first sperm enters

   (c)

   Compare male and female gametes in terms of size and numbers produced.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   After fertilisation, a zygote develops into an embryo, which implants into the lining of the uterus and continues to develop, exchanging substances with the mother's blood via the placenta and umbilical cord throughout the pregnancy.

   (a)

   After fertilisation, a zygote forms and develops into a ball of cells called an embryo, which implants into the lining of the uterus. Describe what happens to the zygote in the days following fertilisation, up to and including implantation.

   [3 marks]

   (b)

   Describe the roles of the placenta and umbilical cord in the exchange of substances between the blood of the mother and the blood of the fetus during pregnancy.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A pregnant woman is advised by her doctor to avoid alcohol, certain medications, smoking and exposure to certain infections during pregnancy, since these can cross the placenta and affect the fetus, and the doctor also explains the hormonal changes that occur in her body during pregnancy.

   (a)

   Explain, using your knowledge of the structure and function of the placenta, why substances that the mother takes into her body can potentially reach and affect the fetus, and discuss why this makes such advice important.

   [6 marks]

   (b)

   The doctor also explains that hormones, including oestrogen and progesterone, are produced throughout pregnancy to maintain the pregnancy and prepare the mother's body for birth. Explain the roles of oestrogen and progesterone during pregnancy, and where these hormones are produced.

   [6 marks]

   Total for question 4: 12 marks

End of questions