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Biology µGCSE:

Sex Determination

10 quick questions - for GCSE and iGCSE



10 minutes maximum! (can you do it in 5?)

Q 1-6: The diagram shows the stages in sexual reproduction in humans.

cell division 1

1. How many chromosomes are in a cell from the cheek of an adult male or female?
  • A. 46
  • B. 23
  • C. 12
  • D. 72
2. How many chromosomes are in a cheek cell from a foetus?
  • A. 23
  • B. 12
  • C. 46
  • D. 72
3. At which stage in the diagram would the cell division called meiosis take place?
  • A. K
  • B. L
  • C. M
  • D. N

4. In which organs does meiosis occur in males and females?

  male female
A testis uterus
B penis ovary
C penis uterus
D testis ovary

5. Using the diagram above, in which stage does fertilisation occur?

6. At which stages in the diagram does mitotic cell division occur?
  • A. K and L
  • B. K and N
  • C. M and L
  • D. M and N
7.Which of the following sex chromosomes would indicate the person was male?
  • A. XX
  • B. YY
  • C. XY
  • D. XXX

8+9: Use this genetic diagram to complete the next two questions:

  male gametes
x y
x i ii
x iii iv

8. Using the information above, which one of the four individuals (i-iv) in the table below has the correct phenotype and genotype?

  Individual phenotype genotype
A i male XX
B ii male XY
C iii male XX
D iv female XY
9. A couple have a child who is a boy. What is the chance that their next baby will be a boy?
  • A. 0
  • B. 25%
  • C. 50%
  • D. 100%

10. A 4 year old girl has a twin brother.

Which of the following statements is not correct?

  • A. The girl has the sex chromosomes XX
  • B. Her brother has the sex chromosomes XY
  • C. The children are identical twins
  • D. The children are non-identical twins.