Topic 9- Sex Determination and Chromosome Disorders Flashcards
Definition of Nondisjunction
the failure of homologous chromosomes or sister chromatids to separate properly during cell division (mitosis/meiosis)
What Nondisjunction does
failure of homologous chromosomes or sister chromatids to separate properly
Definition of Pseudoautosomal
pseudoautosomal regions, PAR1, PAR2, are homologous sequences of nucleotides on the X and Y chromosomes
What Pseudoautosomal does
Homologous sequences of nucleotides on X and Y Chromosome
Definition of Testis-Determining Factor
DNA-binding protein (also known as gene-regulatory protein/ transcription factor) encoded by the SRY gene that is responsible for the initiation of male sex determination in therian mammals (placental mammals and marsupials).
What Testis-Determining Factor does
responsible for the initiation of male sex determination
Definition of Heterochromatin
tightly packed form of DNA or condensed DNA, which comes in multiple varieties.
What Heterochromatin does
tightly packed form of DNA
Definition of Spontaneous abortions
loss of pregnancy naturally before twenty weeks of gestation
What Spontaneous abortions does
loss of pregnancy naturally before twenty weeks of gestation
Definition of Paracentric
an inversion that occurs in a single arm of one chromosome and does not involve the centromere
What Paracentric does
inversion that occurs in a single arm of one chromosome
Definition of Pericentric
an inversion involving the centromere of a chromosome
What Pericentric does
involving the centromere of a chromosome
Definition of Robertsonian
chromosomal abnormality wherein a certain type of a chromosome becomes attached to another
