Looking at the worksheet, I need to solve three different genetics problems. Let me work through each one carefully.
Problem 1: Identify if genotypes are heterozygous (He) or homozygous (Ho)
Homozygous means both alleles are the same (either both capital or both lowercase).
Heterozygous means the alleles are different (one capital, one lowercase).
Let me go through each:
- AA: both capital → Ho
- Ee: different → He
- Ii: different → He
- Mm: different → He
- Bb: different → He
- ff: both lowercase → Ho
- Jj: different → He
- nn: both lowercase → Ho
- Cc: different → He
- Gg: different → He
- KK: both capital → Ho
- oo: both lowercase → Ho
- DD: both capital → Ho
- HH: both capital → Ho
- Ll: different → He
- Pp: different → He
Problem 2: Determine phenotypes from genotypes
For each trait, I need to remember:
- Dominant traits show up with at least one capital letter
- Recessive traits only show up with two lowercase letters
Purple flowers (P) dominant to white (p):
- PP: purple (homozygous dominant)
- Pp: purple (heterozygous - dominant trait shows)
- pp: white (homozygous recessive)
Brown eyes (B) dominant to blue (b):
- BB: brown
- Bb: brown
- bb: blue
Round seeds (R) dominant to wrinkled (r):
- RR: round
- Rr: round
- rr: wrinkled
Bobtails in cats are recessive (t), so long tails are dominant (T):
- TT: long
- Tt: long
- tt: short (bobtail)
Problem 3: List genotypes for each phenotype
Straight hair (T) dominant to curly (t):
- Straight hair can be TT or Tt
- Curly hair must be tt
Pointed heads (T) dominant to round heads (t):
- Pointed heads can be TT or Tt
- Round heads must be tt
Final Answer:
1. AA-Ho, Ee-He, Ii-He, Mm-He, Bb-He, ff-Ho, Jj-He, nn-Ho, Cc-He, Gg-He, KK-Ho, oo-Ho, DD-Ho, HH-Ho, Ll-He, Pp-He
2. Purple flowers: PP-purple, Pp-purple, pp-white; Brown eyes: BB-brown, Bb-brown, bb-blue; Round seeds: RR-round, Rr-round, rr-wrinkled; Cat tails: TT-long, Tt-long, tt-short
3. Straight hair: TT, Tt; Curly hair: tt; Pointed heads: TT, Tt; Round heads: tt
Parent Tip: Review the logic above to help your child master the concept of genetics practice problems simple worksheet.
