Inherited Disorders Flashcards
Desribe a dominant allele
Always be expressed in the phenotype even if there is only one copy present
What’s a recessive allele
Only expressed is two copies are present
What’s cystic fibrosis
Disorder of cell membranes
- allele for normal cell membrane function is dominant-C
- defective cell membranes is recessive-c
How do you get cystic fibrosis
Person must have two copies of the defective allele
What’s polydactyly
People with extra fingers or toes
- caused by dominant allele
Solution to inherited disorders
Embryo screening
=embryos are tested to see if they have the alleles for inherited disorders
= embryos that don’t have defective alleles are implanted into woman
= these develop into healthy offspring
Issues with embryo screening
- expensive
- often a large number of embryos are created but only a small number are implanted
= some healthy embryos destroyed
= unethical
What does a family tree show
Phenotypes
Define allele
Versions of a gene
Describe phenotype
Tells us characteristics caused by persons alleles
Describe homozygous
Person has two copies of same allele
Describe heterozygous
Two different alleles
