Ch 11-3 Flashcards
What is pedigree analysis
A study of a particular trait(s) over generations.
What do vertical lines represent in a pedigree?
They connect one generation to the next
What do horizontal lines represent in a pedigree?
They connect related individuals or individuals who have crossed/reproduced.
What are recessively inherited disorders?
Disorders caused by recessive alleles that code for malfunctioning or absent proteins.
What is a carrier?
A heterozygous individual who carries a recessive allele but does not express the disorder phenotypically
How does consanguinity affect the likelihood of recessive disorders?
It increases the likelihood due to the shared genetic histories of close relatives.
Describe sickle-cell disease
A disorder where a single amino acid change in hemoglobin causes red blood cells to deform.
Why is the sickle-cell allele maintained in some populations?
Heterozygotes have a survival advantage against malaria.
Describe cystic fibrosis.
A lethal genetic disease caused by mutations in a gene encoding a transmembrane protein that transports chloride ions.
What are dominantly inherited disorders?
Disorders caused by dominant alleles, often rare and resulting in decreased reproductive success.
Describe Huntington’s disease.
A neurodegenerative disorder with symptoms appearing later in life (35-40 years old).
What are multifactorial disorders?
Disorders with both genetic and environmental components.
What is genetic counseling?
Counseling provided to couples with family histories of genetic disorders to assess the risk of passing on the disorder to their offspring.
What is the probability of two carriers of a recessive disorder having a child with the disorder?
1/4
What are the ethical implications of genetic screening?
The ability to screen for and potentially alter genetic abnormalities raises significant ethical concerns.
What type of inheritance pattern is represented by a 1:2:1 genotypic ratio and a phenotypic spectrum in the population?
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A) Complete dominance
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B) Incomplete dominance
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C) Codominance
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D) Sex-linked inheritance
B