3.4 Flashcards
what is a genetic disease
disorder caused by a gene in most cases a mutated allele, which alters a protein and impairs normal body functions
recessive
individual must inherit both copies of the disease allele to have the disorder
carriers
carry one copy of a recessive allele
explain cystic fibrosis
- autosomal recessive genetic disease
- caused by a mutation of the CFTR gene on chromosome 7
- produces unusually thick and sticky mucus
- clogs airways and secretary ducts of the digestive system
- leads to respiratory failure and pancreatic cysts
explain Huntington’s disease
- autosomal dominant genetic disease
- mutation of the HTT gene on chromosome 4
- causes progressive neurodegeneration beginning between 30 and 40 years old
- life expectancy is around 20 years after onset of symptoms
explain color blindness
- x-linked recessive
- carried on the X chromosome only
- N: normal n: disease
explain hemophilia
- X-linked recessive
- clotting response to injury doesn’t work
- H: normal h: disease
difference between acquired and inherited traits
acquired: not passed on to the next generation
inherited: passed down from one generation to the next
monohybrid crosses
hybridization cross between pure bred (homozygous) individuals
what is Mendel’s first conclusion (particulate inheritance)
characteristics of both parents are passed on to the next generation as discrete entities (genes)
what is Mendel’s second conclusion (law of segregation)
during gametic meiosis, the two members of any pair of alleles segregate unchanged and are passed into different gametes
what is Mendel’s third conclusion (dominant & recessive alleles)
dominant: always show
recessive: expressed when no other allele is present
state the genotype and phenotype of ABO blood groups
A: IA IA or IA i
B: IB IB or IB i
AB: IA IB
O: ii
