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Flashcards in sex chromosomes Deck (7)
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1

turner syndrome

1 in 3000 females
- Short
- Low hairline
- Broad chest
- Normal intelligence
- Likely sterile

2

poly-X females

1 in 1000 females
- No distinctive features
- Tall and thin
- Few are sterile
- Incidence of mental retardation slightly greater

XXXX and XXXXX
- Normal female anatomy
- Retarded
- Physical problems

3

klinefelter syndrome

- 1 in 1000 males
- Small testes
- Reduced facial and pubic hair
- Tall
- Sterile
- Normal intelligence
Majority is XXY but also XXXY, XXXXY, XXYY

4

animal with XX-XO sex determination

grasshopper

5

animal with ZZ-ZW sex determination

Birds, snakes, amphibiens and fish

6

advantages and stats of the fruit fly

- Small size
- Short generation time of 10 days at room temperature
- Each female lays 400-500 eggs
- Easy to culture in laboratory
- Small genome
- Large chromosomes
- Many mutations available

Size: 2-3 mm in lenght
Anatomy: 3 body segments, 6 legs, 1 pair of wings
Habitat: feeds and reproduces on fruit

7

genome and contribution of genetic of fruit fly

- Chromosomes: 3 pairs of autosomes and X and Y (2n=8)
- Amount of DNA: 175 million base pairs
- Number of genes: 14,000
- % of genes in common with humans: 50%
- Average genze size: 3000 base pairs
- Genome sequenced in year: 2000

Contribution to genetics:
- Basic principles of heredity including sex-linked inheritance, multiple alleles, epistatsis, gene mapping…
- Mutation research
- Chromosome variation and behaviour
- Population genetics
- Genetic control of pattern information
- Behavioral genetics