Chromosomal Mutations and Nondisjunctions
Mistakes of Meiosis
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Chromosomal Mutations occur when there is a change in ______________ of a chromosome.
These can occur due to a _______________ of genes, ______________ of genes, or a change in
the _____________ of genes or a set of genes within a chromosome.
________________________
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______________________ occurs when homologous chromosomes that fail to
separate during meiosis.
The resulting gametes will have either an ____________ (n+1) chromosome or be
__________ (n-1) a chromosome.
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During fertilization, if a gamete with (n+1) chromosomes fuses with a normal
gamete, a condition known as _________________ meaning-3 copies can occur.
During fertilization, if a gamete with (n-1) chromosomes fuses with a normal gamete,
a condition known as _________________ meaning-1copy can occur.
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Individuals with Trisomy will have _____ chromosomes.
Individuals with Monosomy will have _____ chromosomes.
Three of the most common conditions caused by NONDISJUNCTION are:
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A ________________________ is a chart/picture that shows an individual’s
chromosomes.
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From this chart, a trained individual can tell if a person is ____________, or has an
_________________ chromosome, the _____________ of the person/baby, and in
some cases ______________/_____________ that may occur within a single
chromosome depending on it’s size.
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The _________ chromosomes are the 23rd pair of chromosmes.
The remaining 22 pairs of chromosomes that do not carry genes for gender are
known as ___________________ .
In males, the chromosomes are _____-homologous and are symbolized with __ __
In females, the chromosomes are completely homologous and symbolized __ __
During fertilization the __________ will determine the gender.
 Nondisjunction of the 21st chromosome can result in _________ __________
 This is the most common of chromosomal abnormalities occurring ________
births.
 The risk of passing on a gamete with a nondisjunction of chromosomes increases
significantly with the ____________ of the female at the time of
conception/fertilization.
 Failure of the X (female) chromosomes to segregate during meiosis can result in
______________________ syndrome in males and _______________ syndrome
in females.
 Failure of the Y (male) chromosome to segregate during meiosis can result in an
__ __ __ male, but there is no name currently assigned to this condition. However
research indicates that individuals who have this condition could possibly be more
prone to violent behavior but not enough evidence to support any theories.