1. For each genotype below, indicate whether it is a heterozygous (He) OR homozygous (Ho).
TT Ho
Bb He
DD Ho
Ff He
tt Ho
dd Ho
Dd He
ff Ho
Tt He
bb Ho
BB Ho
FF Ho
Which of the genotypes in #1 would be considered purebred? TT, DD, tt, dd, ff, bb, BB, FF
Which of the genotypes in #1 would be hybrids? Dd, Bb, Ff, Tt
2. Determine the phenotype for each genotype using the information provided about SpongeBob.
Yellow body color is dominant to blue.
YY yellow
Yy yellow
yy blue
Square shape is dominant to round.
SS square
Ss square
ss round
3. For each phenotype, give the genotypes that are possible for Patrick.
A tall head (T) is dominant to short (t).
Tall = TT, Tt
Short = tt
Pink body color (P) is dominant to yellow (p).
Pink body = PP, Pp
Yellow body = pp
4. SpongeBob SquarePants recently met SpongeSusie Roundpants at a dance. SpongeBob is heterozygous for his square shape, but SpongeSusie is round. Create a Punnett square to show the possibilities that would result if SpongeBob and SpongeSusie had children. HINT: Read question #2!
Punnett Square:
S s
S SS Ss
s Ss ss
A. List the possible genotypes and phenotypes for their children.
SS (square), Ss (square), ss (round)
B. What are the chances of a child with a square shape? 2 out of 4 or 50%
C. What are the chances of a child with a round shape? 2 out of 4 or 50%
5. Patrick met Patti at the dance. Both of them are heterozygous for their pink body color, which is dominant over a yellow body color. Create a Punnett square to show the possibilities that would result if Patrick and Patti had children. HINT: Read question #3!
Punnett Square:
P p
P PP Pp
p Pp pp
A. List the possible genotypes and phenotypes for their children.
PP (pink), Pp (pink), pp (yellow)
B. What are the chances of a child with a pink body? 3 out of 4 or 75%
C. What are the chances of a child with a yellow body? 1 out of 4 or 25%
Parent Tip: Review the logic above to help your child master the concept of spongebob genetics worksheet.
