Unit 2 Exam Flashcards
In a family that starts with you, your grandchildren would be the _____ generation.
F2
In a human pedigree that traces the inheritance of albinism, a filled square represents a _____.
Male with albinism
A person who has two identical alleles for a particular gene is _____ for that gene.
Homozygous
This pedigree shows the transmission of an autosomal recessive disease. If individuals III-2 and III-3 have an additional child, what is the probability that it will be an affected girl?
1/8
This pedigree shows the transmission of an autosomal recessive disease. What is the genotype of individual II-3 if the genes are represented by A/a?
Aa
Mendel called physical units responsible for the inheritance of traits “elementen.” The basis for his first law is that elementen _____.
Separate from each other as gametes form
For two genes on different chromosomes, the inheritance of one gene does not influence the chance of inheriting the other gene. This is called _____.
The law of independent assortment
For two traits A and B with two alleles each, the genotypes of the gametes that a double heterozygote would produce are _____.
AB, Ab, aB, ab
The phenotypic ratio expected from a dihybrid cross is _____.
9:3:3:1
Gregor Mendel is known for _____.
Breeding plants to demonstrate the logic behind inherited trait transmission
When Mendel crossed pure breeding peas having yellow seed color (YY) with pure breeding peas having green seed color (yy), all of the offspring had yellow seed color. These results mean that yellow seed color is the _____.
Dominant phenotype
The difference in mode of inheritance between Huntington disease and cystic fibrosis is that _____.
Huntington disease does not skip generations, but cystic fibrosis can
Destiny has distal symphalangism - her fingers and toes are stiff, with tiny nails. She looks it up and finds it is an autosomal dominant trait. Since her parents do not have it, she reasons that she has a new mutation. However, if she has children, each of them, assuming her partner does not have the condition, has a(n) _____ probability of inheriting the condition.
1/2
Which of the following analyses would be most effective in identifying a disease-causing gene variant inherited from a parent, or one that has arisen in the child?
Family exome analysis
Cystic fibrosis is autosomal recessive. This means that _____.
Both sexes can be affected and can “skip” generations through carriers
Which of the following genotypes is homozygous?
RR
In pea plants, the allele for tall (T) is dominant to the allele for short (t). The genotype for a short pea plant is _____.
tt
Which of the following is an illness caused by a mutation in mitochondrial DNA?
Leigh syndrome
Marbles is a Manx cat whose tail is so short that she appears not to have one. The genotype for short tail in Manx cats is heterozygous (Mm). Cats that are genotype mm have normal length tails, but cats that are genotype MM die before birth due to highly abnormal brains and spinal cords. Marbles has one copy of a dominant _____ allele.
Lethal