Chapter 9 Flashcards
(11 cards)
What are the different types of chromosomal mutations?
deletion, duplication, inversion, translocation
What is haploinsufficiency?
a condition where having only one copy a gene (1x - haploid for gene) does not result in the wild type phenotype, but results in an abnormal phenotype
What is the difference between a paracentric and a pericentric inversion?
a paracentric does not include the centromere in the inversion and a pericentric includes the centromere
What is a Robertsonian translocation?
two acrocentric chromosomes are combined into one large metacentric chromosome and a small chromosome fragment that may be lost
What are the four types of aneuploidy?
nullisomy, trisomy, monosomy, tetrasomy
What is the difference between primary and familial down syndrome?
primary - trisomy 21
familial - results from a translocation of chromosome 21 with another chromosome - usually 14 or 15
What is uniparental disomy?
the inheritance of both chromosomes of a homologous pair from a parent - usually starts as a trisomy, but since most autosomal trisomys are lethal, they lose one. If the two remaining chromosomes are from the same parent, that is uniparental disomy
What is mosaicism?
a condition in which regions of tissue within a single individual have different chromosome constitutions. nondisjunction in a mitotic division may generate patches of cells in which every cell has a chromosome abnormality and other patches in which every cell has a normal karyotype
If humans and chimpanzees have the same genes, and humans have 46 chromosomes and chimpanzees have 48 chromosomes, then it is reasonable to assume that the human chromosome number was reduced through:
Robertsonian translocation
Which is most likely to increase the protein product for one or more genes?
polyploidy
