Genetics puzzle
Basic questions
1. What does heterozygous mean?
2. What does homozygous mean?
3. What does dominant mean?
4. What does recessive mean?
5. Take a look at the picture on the right.
Explain how it is possible that a father
and mother with brown eyes, can have
a child with blue eyes.
Puzzles
Puzzle 1
Anisha is homozygous recessive for eye colour. She has blue eyes. Marco is heterozygous for
eye colour. They have children. Yara is the firstborn and she has blue eyes. The second child
is Daniel. He has brown eyes.

Write down for every person the phenotype and the genotype. Use the letter A/a.
Puzzle 2
Laila and Bob have a daughter, Carly. Both Laila and Bob have brown eyes, but Carly has blue
eyes.

Write down the genotype for both Laila and Bob. Use the letter A/a. Also, explain
which allele is dominant.
Puzzle 3
Gerard and Alexandra are both healthy and have a kid together. Unfortunately, this kid has
an inherited illness.

Write down the genotype for every person for this illness. Use the letter B/b. Also,
explain how the kid can be ill whereas the parents are healthy.