chapter 10 part 1 Flashcards
Chromosomes do not occupy the same territory in each nucleus, they are found in _______
territories
_________ domains are regions between the chromosome territories
inter-chromosomal
Interchromosomal domains are channels for movement of _______, _______, _______
proteins
enzymes
RNA molecules
What is a karyotype?
the number and visual appearance of the chromosomes
_______ uses molecular probes labeled with fluorescence to detect their target sequence
In situ hybridization (FISH)
What does p stand for on a chromosome?
short arm
What does q stand for on a chromosome?
long arm
_______: the centromere is near the middle of the chromosome
metacentric
_______: the centromere is between the center and the tip
submetacentric
_______: the centromere is close to one end
acrocentric
_______: the centromere is at the tip of the chromosome and there is no p arm
telocentric
________: a piece of DNA without a centromere
acentric
Compare heterochromatin and euchromatin:
1) condensation
2) silenced and expressed genes
3) type of staining
4) repitition of DNA
1) heterochromatin more condensed than euchromatin
2) hetero silenced (methylated), eu expressed (acetylated)
3) hetero = dark, eu = light
4) hetero = more repetitive, eu = less repetitive
The standard for human chromosome banding is _______; the patterns are distinct and reproducible
G (Giemsa) banding
What does 1q3.2.3 tell you
chromosome 1, arm q, region 3.2.3
_______ is the failure of homologous chromosomes or sister chromatids to separate as they normally do during cell division
chromosome nondisjunction
Nondisjunction in meiosis I results in:
2 (n+1) gametes
2 (n-1) gametes
- all gametes are affected
Nondisjunction in meiosis II results in:
1 (n+1) gamete
1 (n-1) gamete
2 normal gametes
changes in _______ lead to an imbalance of gene products from the affected chromosome relative to the unaffected chromosome
gene dosage
What are the 3 autosomal aneuploidy diseases?
1) trisomy 13 (patau)
2) trisomy 18 (edward)
3) trisomy 21 (down)
What is the term for the sex-chromosome aneuploidy XXY?
Klinefelter’s syndrome
What is the term for the sex-chromosome aneuploidy XYY?
Jacob syndrome
What is the term for the sex-chromosome aneuploidy XXX?
triple X syndrome
What is the term for the sex-chromosome aneuploidy XO?
Turner syndrome
_______ occurs due to the presence of the anomalous extra isochromosome 12p
Pallister-Killian syndrome
An _______ is an unbalanced structural abnormality in which the arms of the chromosome are mirror images of each other
isochrome
Pallister-Killian syndrome leads to the development of _______
tetrasomy 12p
Because not all cells have the extra isochromosome, Pallister-Killian syndrome is a _______ condition
mosaic
Research has identified a link between the risk of trisomy 21 and _______
maternal age
a portion of the chromosome called the _______ can be correlated with the majority of the Down syndrome symptoms
DSCR (down syndrome critical region)
A candidate gene _______, known to produce dosage-sensitive learning defects in mice and flies, makes a major contribution to Down syndrome
DYRK
In XO embryos, the single copy of the gene _______, which is not inactivated by dosage compensation, is insufficient to direct normal development (what in particular?)
SHOX
infertility (sterile)
_______ can develop as a result of mitotic nondisjunction early in embryogenesis
- 25% of Turner syndrome cases are the result of this with 46 XX cells, 45 XO, and 47 XXX
mosaicism
A rare abnormality, _______ sometimes occurs in humans, and is when both copies of a homologous chromosome are from the same parent
Uniparental Disomy (UPD)
In a process called _______, one copy of the trisomy chromosome is randomly ejected in one of the first mitotic division after fertilization. If the two copies retained by the zygote are from the same parent, _______ results
trisomy rescue
uniparental disomy
_______ is the presence of three or more whole sets of chromosomes in the nucleus of an organism
polyploidy
Polyploidy that results from duplication of chromosome sets within a species is called _______
autopolyploidy
Polyploidy that results from duplication of chromosome sets of different species is called _______
allopolyploidy
Allopolyploidy involves sets of partially homologous chromosomes called _______ and results in _______ the amount of chromosomes
homeologous
double
_______ wanted plant with cabbage leaves and radish roots
G. Karpechenko
_______: an interspecific hybrid having a complete diploid set from each parent form
amphidiploid
