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14. Pedigrees/ Human Genetics. Fruit Fly- Drosophila melanogaster, used by scientists to study genes and heredity. Advantages of Fruit Flies Short Life Span Small and easy to maintain 8 Chromosomes. Human Chromosomes - 46 total (23 pairs).
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Fruit Fly-Drosophila melanogaster, used by scientists to study genes and heredity. Advantages of Fruit Flies Short Life Span Small and easy to maintain 8 Chromosomes
Human Chromosomes- 46 total (23 pairs) Autosome- 22 pairs of non-sex cells determining traits. Sex Chromosomes- one pair of chromosomes determining gender.
Karyotype Karyotype- picture of all the chromosomes lined up during metaphase taken about half way through pregnancy used to determine a chromosomal abnormality. (blood cells)
Determining Sex Male- XY Female- XX Sex-Linked Traits- traits caused by genes that are located on the sex chromosomes. Ex. Color Blindness, Pattern Baldness, Hemophilia Why Males are affected more than females X chromosome is larger than Y chromosome so it holds more genes. Both X’s must have gene to be expressed in females whereas only one X in a male must have gene to be expressed.
Pedigree Analysis Pedigree Analysis- diagram of a family history that shows how one trait is passed through several generations. *Used by healthcare workers to help parents determine the likelihood of passing on genetic disorders.
Symbols of a Pedigree O = Female = Male / = Affected female/ male ___ = Marriage = Offspring
Rules of a Pedigree Fill in the shaded people with homozygous recessive (rr). The non-shaded in people will receive at least one capital. Determine the second letter on the non-shaded in people by looking at parents, siblings and children