Transcript How do animals get energy?

Chromosomes and
Inheritance
Chapter 12 (231-241)
Parts of Chromosomes
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Telomeres
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Centromeres
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Locus
Telomeres
p arm
q arm
Telomeres
Karyotype

Picture of
chromosomes
 Homologous
chromosomes
contain the same
genes
 Often arranged
with autosomes
(found in both
sexes) in
descending order
and sex
chromosomes
separate
X-Linked Inheritance
Color blindness
(X-linked recessive)
Hemophilia
(X-linked recessive)
Autosomal Recessive Disorders
Sickle-Cell Anemia
Red blood cells take on a
curved shape
Clot in the capillaries
Decreased oxygen supply to
brain & muscles
Werner Syndrome
Premature aging
Begins during adolescence
Mapped to chromosome 8
Autosomal Dominant Disorders
Polydactyly
Extra fingers or toes
Achondroplasia
Growth related defect
Cartilage growth in the long
bones is slow
Results in short stature
Retinitis Pigmentosa
X-linked recessive, Autosomal dominant or
Autosomal recessive
Eye diseases that affect the retina
Degeneration of cones and rods in the eye
Loss peripheral vision
Pedigree Analysis
Diagrams of family history
Used to determine if a disease or condition
is dominant, recessive, or X-linked
Use symbols to represent individuals
Polyploidy
The addition of one or more sets of
chromosomes to a genome
Malfunction in meiosis
Egg or sperm end up with two sets of
chromosomes
Detrimental in humans
Preferred in some plant species
Aneuploidy
One chromosome too many or missing
one chromosome
Common in humans
Common in miscarriages
Ex. Down syndrome
Result of nondisjunction
Nondisjunction
Most result in a miscarriage, except for those
that occur on chromosome 13, 18, or 21
Trisomy
Zygote ends
up with 3
chromosomes
instead of 2
for a given
pair of
chromosome.
Down Syndrome (Trisomy 21)
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1 in 800-1,000 births
Large tongue
Flat face
Single crease across
palm
Slanted eyes
Mental retardation
-Some are not
Increased risk for
congenital hear defects
and leukemia
Edward Syndrome (Trisomy 18)
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1 in 3,000 births
Affects more girls than
boys
Heart defects
Displaced liver
Clenched hands
Low-set ears
Severe retardation
98% abort
Lifespan < 1 year
Patau Syndrome (Trisomy 13)
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1 in 10,000 births
Cleft lip and palate
Small eyes
Extra fingers & toes
– polydactylism
Defects
– Heart
– Brain
– Kidney
Most abort
Live span < 1 month
Klinefelter
Syndrome
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1 in 500-1,000 births
 Breast development
 Small testes
 Sterile
 Autoimmune
disorders
 Low intelligence
– Not retarded
Turner Syndrome

1 in 2,500 births
 Short
 Not go through puberty
 Webbed neck
 Dropping eyelids
 Produce little estrogen
 Sterile
 Increased risk for
obesity, cataracts,
arthritis, scoliosis
Aberrations within chromosomes
Deletions:
Ex. Cri-du-chat syndrome
Inversions:
Ex. Acute Myeloid Leukemia
Translocations:
Duplications:
Deletion

Part of a
chromosome is
deleted
Cat Cry Syndrome
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Deletion on chromosome 5
Prader-Willi Syndrome
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Deletion on chromosome 15
Inversion
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A
B
C
D
E
A
B
C
D
E
F
G
H
I
J
F
I
H
G
J
Part of a
chromosome is
inverted
Inversion of Chromosome 16
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Inversion between
chromosome 13 and 22
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Acute myeloid leukemia
Translocation

Part of a
chromosome
attaches to a
nonhomologous
chromosome
Translocation of Between
Chromosomes 1 and 3
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Part of chromosome 3
attached to
chromosome 1
Acute myeloid leukemia
Duplication
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Part of a
chromosome is
duplicated
Chromosome 10q duplication
syndrome
Mental retardation
 Defects in many organs
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– Heart
– Kidneys
– Bones
– Muscles
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Life span less than 1 year