Notes: Chromosomes and Chromosome Disorders

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Notes Chromosomesand Chromosome Disorders
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Characteristics

• Chromosomes are long, threadlike groups of genes
  made up of DNA found in the nucleus.
• Chromosomes are always an even number
• Examples Humans 46
• Dogs 78
• Mosquitoes 6
• Goldfish 94
• Each chromosome has many genes on it!

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Human Chromosomes

• Each person has 46 chromosomes
• (23 from your mom and 23 from your dad)
• 1. Autosomes first 22 pairs (44 total)
• 2. Sex Chromosomes 23rd pair (2 total)
• XX female
• XY male

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Amniocentesis

• One way to detect genetic defects is to obtain
  fetal cells through a needle inserted in the
  amniotic sac of a pregnant woman.

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Karyotype

• A method of organizing the chromosomes of a cell
  in relation to size.
• It is a tool used to help detect genetic defects

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Mutations

• Downs syndrome extra 21 chromosome mental
  deficiencies, short stature, short wide neck,
  stocky arms and legs, sterile.
• Turners syndrome XO (females with only one X)
  they are shorter than normal.
• Klinefleters syndrome XXY (males with an
  extra X chromosome) they are taller than normal.
• Cri-du-chat (French for Cry of the Cat). Missing
  part of chromosome 5. When babies are born with
  this they sound like a cat crying. Downward slant
  to the eyes, Low birth weight, mental
  deficiencies, Skin tags just in front of the ear,
  small head, small jaw, Wide-set eyes

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What disorder?Male or female?

• Cri-du chat

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What disorder?Male or female?

• Downs syndrome
• Female

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What disorderMale or female?
Turners syndrome Female
Sisters.one with Turners syndrome
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What disorder?Male or female?

• Kleinfelters Syndrome
• male