Download Coin Child Lab – Answer Sheet

Coin Child Lab
BACKGROUND INFORMATION:
In this lab, you will see how certain traits are the result of different combinations of genes.
Genes are units of heredity – the passing of traits to offspring. Each organism has genes from both
parents that determine their characteristics. One gene may hide, or mask, another gene; it is the
dominant gene. A gene that is hidden is a recessive gene. Dominant genes are written as capital letters
while recessive genes are written as lowercase letters. Genotype shows the genes that have been
passed along while phenotype is the actual observable trait that is the result of the genotype.
If the genes for a given trait are both dominant or both recessive, we use the term homozygous
or purebred. Heterozygous or hybrid means that one dominant gene and one recessive gene is present,
but the recessive gene is hidden. Some genes are neither dominant nor recessive; they show
incomplete dominance. There are also some traits that are passed down through polygenic inheritance.
Polygenic inheritance occurs when one trait is determined by multiple genes, not just one gene (multiple
pairs of alleles, not just one pair).
DIRECTIONS:
1. First, you will work in a team of two to produce the initial offspring and then combine with
another group to produce punnett squares for possible future offspring. You will determine the
gender of your child. The youngest person in the lab group will flip their coin - if you flip heads,
this will represent XX chromosomes and the child will be a female. If you flip tails, this will
represent XY chromosomes and the child will be a male. The other pair in the lab group will
record their child as the opposite sex. Record the genotype XX or XY and the phenotype
(female or male) in your answer sheet.
*In real life, it is only the male sperm cell that determines the sex of the offspring.
This is because egg cells only carry an X chromosome and sperm cells carry either an X
chromosome or a Y chromosome.
2. For the remaining traits, both partners (of the initial pair) will flip their coin. HEADS will be
the dominant gene while TAILS will be the recessive gene. Combine the two coin flips & record
the genotype and phenotype for each trait on your answer sheet.
3. To determine the color of hair and eyes – both partners will flip their coin twice. Record the
genes from the first flip, then record the genes for the second flip. Compare the combinations
of the four genes to the color scales shown and record the phenotype.
4. Once all traits are completed, draw and color the face of your offspring to match the traits you
flipped for today. Write the name of the child under the face.
Use the chart on the back of this handout to
determine your traits!
Name:
Coin Child Lab – Answer Sheet
TRAIT
Period:
GENOTYPE
GENOTYPE
[from coin toss]
Dominant
(Heads)
[from coin toss]
Dominant
(Heads)
PHENOTYPE
OBSERVED
TRAIT
Recessive
(Tails)
Sex of child
[toss one coin]
1. Shape of
face
2. Chin cleft
3. Hair
PHENOTYPE
OBSERVED
Recessive
(Tails)
11. Length of
lashes
12. Shape of
eyebrows
13. Position of
eyebrows
14. Color of
eyebrows
4. Widow’s
peak
15. Size of nose
5. Color of hair
16. Size of ears
6. Spacing of
eyes
7. Shape of
eyes
8. Position of
eyes
17. Shape of
lips
18. Size of
mouth
9. Size of eyes
20. Dimples
19. Freckles
10. Eye color
Lab Questions:
21. Define genotype.
22. Define phenotype.
23. Give an example of a genotype that your coin child has that is heterozygous. __________
Describe the phenotype for this genotype ____________________________
24. Give an example of a genotype that your coin child has that is homozygous dominant. __________
Describe the phenotype for this genotype ____________________________
25. Give an example of a genotype that your coin child has that is homozygous recessive. __________
Describe the phenotype for this genotype ____________________________
Part 2 of Lab: Match up with the pair in your lab group to make punnett squares for your
potential offspring. You must complete and give the correct percentages for each trait
except hair and eye color
26. Face Shape
27. Cleft Chin
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
28. Hair
29. Widow’s peak
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
30. Spacing of eyes
31. Shape of eyes
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
32. Position of eyes
_______% dominant trait
_______% recessive trait
33. Size of eyes
_______% dominant trait
_______% recessive trait
34. Length of lashes
35. Shape of eyebrows
eyeyeeyebeyebrowns
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
36. Position of eyebrows
eyebrowneyebeyebrowns
_______% dominant trait
_______% recessive trait
37. Color of eyebrows
_______% dominant trait
_______% recessive trait
38. Size of nose
39. Size of ears
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
40. Shape of lips
41. Size of mouth
_______% dominant trait
_______% dominant trait
_______% recessive trait
_______% recessive trait
42. Freckles
43. Dimples
_______% dominant trait
______% dominant trait
_______% recessive trait
______% recessive trait
44 & 45 Draw your initial child.