Inheritance

• What are inherited disorders?


  Disorders that can be passed down from parents to offspring.
• What is cystic fibrosis?


  A genetic disorder that causes thick sticky mucus in air passages and the pancreas.
• What type of allele causes cystic fibrosis?


  A recessive allele.
• What does it mean to be a carrier of cystic fibrosis?


  It means having one copy of the recessive allele without showing symptoms of the disorder.
• What is the requirement for a child to inherit cystic fibrosis?


  Both parents must be carriers or have the disorder themselves.
• What is the probability of a child having cystic fibrosis if both parents are carriers?


  There is a 1 in 4 chance.
• What is polydactyly?


  A genetic disorder where a baby is born with extra fingers or toes.
• What type of allele causes polydactyly?


  A dominant allele.
• What is the likelihood of a child having polydactyly if one parent carries the dominant allele?


  There is a 50% chance.
• What can be detected through embryo screening?


  Many genetic disorders, such as cystic fibrosis.
• What are some ethical concerns surrounding embryo screening?


  It may imply that individuals with genetic disorders are undesirable.
• What are the arguments for and against embryo screening?


  **Against:**

  • Implies genetic problems are undesirable.
  • Could lead to selecting for 'desirable' traits.
  • Screening is expensive.

  
  

  **For:**

  • Helps prevent suffering.
  • Reduces government healthcare costs.
  • Laws prevent excessive selection (e.g., sex selection).
• What characteristics are determined only by genes?


  Examples include eye color and inherited disorders.
• What is an allele


  Different versions of a gene eg allele for blue eyes
• What is homozygous 


  Two copies of the same characteristic eg: blue and blue eyes
• What is homologous 


  Chromosomes for a specific part , not always same trait. Eg: Eye+Eye
• What is heterozygous 


  Alleles for a characteristic that are different eg: blue and brown eyes
• What is a phenotype 


  Seen characteristics that you carry from your genotype
• What is genotype


  All the specific genes a person carries