Sex determination and sex-linked traits

Explain how X and Y chromosomes determine biological sex and predict the inheritance of X-linked traits such as colour blindness.

⏱ 20 min❓ 8 questions

What you'll be able to do

✔I can explain how X and Y chromosomes determine biological sex in humans
✔I can explain why X-linked recessive traits are more common in males
✔I can use Punnett squares with X and Y chromosomes to predict offspring

How this works

1Read the short explanations first — they teach you what you need before each question.
2Answer each question, then tap Check. A right answer moves you on automatically; if it's wrong, you'll see a friendly explanation of why.
3Finish all 3 steps to see your score — sign in and subscribe to unlock the full lesson and save it.

What's inside

8 questions and 1 quick teaching card, including:

🔘Multiple choice — Tap the answer you think is best, then check it.
⚖️True or false — Read the statement and decide if it's true or false.

👪Grown-up tip: sit alongside younger learners for the first few lessons. Read the questions together and chat about the explanations — that's where the real learning sticks.

Curriculum: AC9S10U01