Inheritance & EvolutionStudy Notes
Two Inherited Disorders for AQA
Part of Inherited Disorders — GCSE Biology
This study notes covers Two Inherited Disorders for AQA within Inherited Disorders for GCSE Biology. Genetic disorders, family pedigrees, and probability calculations It is section 1 of 10 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 1 of 10
Practice
25 questions
Recall
20 flashcards
Two Inherited Disorders for AQA
CYSTIC FIBROSIS (Recessive)
Caused by: Recessive allele (ff) — both parents must be carriers
Effects:
- Thick, sticky mucus in lungs and digestive system
- Difficulty breathing, frequent infections
- Digestive problems (enzymes can't reach food)
Inheritance: If both parents are carriers (Ff), 25% chance of affected child
POLYDACTYLY (Dominant)
Caused by: Dominant allele (P) — only one copy needed
Effects:
- Extra fingers or toes
- Can be surgically corrected
- Not usually harmful
Inheritance: If one parent has Pp, 50% chance of affected child