1: How many chromosomes does a normal body cell have?

21
23
44
46

2: Which of these features is only affected by your genes?

strength
blood group
hair length
height

3: If a sperm with an X chromosome fertilizes an egg, what sex will the baby be?

girl
boy
equal chance of either a girl or a boy
depends on whether the egg has an X or a Y chromosome

4: Which of these features is not affected by your genes?

Your natural hair colour
Which language you speak
The sound of your voice
How high you grow

5: About how many different genes does it take to make a person?

3 000
300 000
30 000
300

6: What are different versions of a particular gene called?

alleles
chromosomes
gametes
analogues

7: What is the scientific name for sex cells (sperm and egg cells)?

chromosomes
alleles
zygotes
gametes

8: A girl has one allele for blue eyes and one for brown eyes. What colour will her eyes be?

a mixture of blue and brown
brown
blue
could be either

9: Which sorts of cells have only one out of each pair of chromosomes?

muscle cells
nerve cells
blood cells
gametes

10: What affects your final height?

genes, diet and health
genes only
diet and health only
genes and health only