Name: ______________________________ Period: ________ Date: __________________
Chromosomal Mutations & their effects
Karyotype
• A picture of the chromosomes of an individual or
a species, including ________________, form,
and ______________ of the chromosomes.
• Often used to diagnosis chromosomal
abnormalities.
Chromosomes
• Humans have ___________________
– 22 pairs are ____________________
– 1 pair are sex chromosomes
• (women = XX, men = XY)
• Chromosomes have a __________________ that
holds the ___________________ (two parts of the
chromosome together).
• The top ½ of the chromosome is called the “___”
arm and the bottom ½ is “___”
Nondisjunction Disorder
• Nondisjunction is the failure of chromosome pairs to separate during
___________________ (making of gametes – sex cells)
• it can cause some gametes to gain an extra chromosome and others to lose one
• _________________ = A chromosome having no homologue (matching
chromosome)
• ___________________ =The condition of having three copies of a given
chromosome in each __________________ (body) cell rather than the normal
number of two.
Aneuploidy =
_________________________________
_________________________________
_________________________________
Turners Syndrome
 1 in 5,000 births
 45 chromosomes - X only
 #23 Monosomy Nondisjunction
 96-98% do not survive to birth
 No menstruation
 No breast development
 No hips
 Broad shoulders and neck
Jacob’s Syndrome
 1 in 1,800 births
 47 chromosomes - XYY only
 #23 Trisomy Nondisjunction
 Normal physically
 Normal mentally
 Increase in testosterone
 More aggressive
 Normal lifespan
Cri-Du-Chat Syndrome
 1 in 216,000 births
 46 chromosomes - XY or XX
 #5 Deletion of upper arm (p deletion)
 Moon-shaped face
 Heart disease
 Mentally retarded
 Malformed larynx
 Normal lifespa
Kleinfelter Syndrome
 1 in 1,100 births
 47 chromosomes XXY only
 #23 Trisomy Nondisjunction
 Scarce beard
 Longer fingers and arms
 Sterile
 Delicate skin
 Low mental ability
 Normal lifespan
Prader-Willi Syndrome
 1 in 5,000,000 births
 46 chromosomes XY=97% XX=3%
 #15 Deletion of lower arm (q deletion)
 Small bird-like head
 Mentally retarded
 Respiratory problems
 Obesity
 Short lifespan
Triple X Syndrome
 1 in 2,500 births
 47 chromosomes XXX only
 #23 Trisomy Nondisjunction
 Normally physically
 Normal mentally
 Tall
 Fertile
 normal lifespan
Down Syndrome
 1 in 31,000 births
 46 chromosomes XY=97% XX=3%
 #14/21 Translocation
Down Syndrome Trisomy
 1 in 1,250 births
 47 chromosomes - XY or XX
 #21 Trisomy Nondisjunction
 Short, broad hands
 Stubby fingers
 Rough skin
 Impotency in males
 Mentally retarded
 Small round face
 Protruding tongue
 Short lifespan
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