Show in a chart the result of cross between pure long(LL) winged drosophila and pure short (ll) winged drosophila up to second filial generation.

Genetic Cross Between Pure Long-Winged (LL) and Pure Short-Winged (ll) Drosophila

1. Parental (P) Generation

• Parental Cross: LL (long-winged, homozygous dominant) × ll (short-winged, homozygous recessive)
• Gametes:
  • LL produces L (only dominant allele).
  • ll produces l (only recessive allele).
• Offspring (F₁ Generation): All offspring are heterozygous (Ll) and exhibit the long-winged phenotype (since L is dominant over l).

2. First Filial (F₁) Generation

• F₁ Cross: Ll (long-winged) × Ll (long-winged)
• Gametes:
  • Each Ll parent produces L and l in equal proportions (50% each).
• Punnett Square:

      |   L   |   l
  ----|-------|-------
  L   | LL    | Ll
  l   | Ll    | ll
  

• Genotypic Ratio (F₂ Generation): 1 LL : 2 Ll : 1 ll
• Phenotypic Ratio (F₂ Generation):
  • LL (Long-winged) → 25%
  • Ll (Long-winged) → 50%
  • ll (Short-winged) → 25%
  • Final Phenotypic Ratio: 3 Long-winged : 1 Short-winged

3. Explanation of Results

• Dominance: The L allele is dominant, so all Ll and LL individuals show the long-winged trait.
• Recessiveness: Only ll individuals express the short-winged trait.
• Mendelian Inheritance: The cross follows Mendel’s Law of Segregation (alleles separate during gamete formation) and Law of Independent Assortment (if considering multiple traits).

4. Summary of Generations

LL+llF₁ crossLl+Ll

This cross demonstrates complete dominance and the 3:1 phenotypic ratio in the second filial generation.