
Pictured above is an alien who displays all of the dominant
characteristics of its species. Below is a chart listing various traits
found in this alien race. Use the information in the chart to solve the
genetics problems that follow.
| Trait | Dominant Phenotype | Recessive Phenotype |
| Body color | (Y) Yellow | (y) Orange |
| # of Antennae | (A) 2 | (a) 1 |
| Eye color | (P) Purple | (p) White |
| Eyesight | (E) Glasses needed | (e) Glasses not worn |
| # of Body Rings | (R) 3 | (r) 5 |
1. A heterozygous male mates with a pure yellow female. What is the chance this couple will produce an orange baby? answer
2. Two purple-eyed aliens mate. Both aliens are hybrid for the eye color trait. What is the chance this couple will produce a baby with a homozygous recessive genotype? answer
3. A heterozygous female with 3 body rings mates with a 5-ringed male. What is the chance that this couple will have a baby that looks like its mother? answer
4. A pure male alien displaying the dominant body color mates with a female that is homozygous recessive for this characteristic. What is the chance that this couple will have a baby with a hybrid genotype? answer
5. A male alien with 1 antenna mates with a female alien who has 2 antennae. The female is heterozygous for the antenna trait. What is the chance that this couple will produce a baby with the recessive phenotype? answer
6. An alien couple, both of which wear glasses, are having a baby. The male's genotype is heterozygous. The female is phenotypically dominant but does carry the recessive allele. What is the chance that this couple's baby will have to wear glasses? answer
7. A 3-ringed female mates with a homozygous male.
The female has been genetically tested and is carrying both the dominant and the
recessive allele for this trait. The male displays the recessive
phenotype. What is the chance that this couple will have a genetically
pure baby? answer
1. male = Yy female = YY
chance of orange baby (yy) = 0%
2. male = Pp female = Pp
chance of baby with homozygous recessive genotype (pp) = 25%
3. male = rr female = Rr
chance of baby looking like mom - e.g. having 3 rings (RR or Rr) = 50%
4. male = YY female = yy
chance of baby having hybrid gentotype (Yy) = 100%
5. male = aa female = Aa
chance of baby with recessive phenotype - e.g. 1 antenna (aa) = 50%
6. male = Ee female = Ee
chance of baby wearing glasses (EE or Ee) = 75%
7. male = rr female = Rr
chance of genetically pure baby (RR or rr) = 50%