Title: Euploidy
1Euploidy
- Describing a nucleus, cell or organism that has
an exact multiple of the haploid number (n) of
chromosomes. - For example diploid (2n), triploid(3n), and
tetraploid (4n) nuclei or cell are euploid
Compare aneuploidy
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2Aneuploidy
- Describing a nucleus, cell or organism in which
one or more chromosomes have been added to or
deleted from the complete set, so that the total
number of chromosomes is not exact multiple of
the haploid number (n) - For example 2n1 (trisomy), 2n-1 (monosomy
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3EUPLOIDY
- Changes of the chromosome number which involved
the whole chromosome set - Occurred when a set of chromosome did not
separate during gametogenesis -
- Common in plants than in animals
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4- Gametes fusion will produce cell _at_ organism which
have more than 2 set of chromosome - Cell with 3 or more chromosome set
- polyploid
- 2 types of polyploidy
- i) Autopolyploidy
- ii) Allopolyploidy
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5Polyploidy
- The condition of having more than two sets of
chromosomes ( 3n, 4n, 5n, )
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6TRIPLOID
- Triploid (3n) occurs when
- i) a gamete (2n) fused with a normal gamete (n)
- ii) chromosomes disable to segregate during
meiosis to produce diploid gamete - iii) gamete from tetraploid organism (4n) fused
with diploid organism gamete (2n).
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7TETRAPLOID
- Tetraploid plants can be produced by
- 1) Somatic duplication of chromosome number
- i) Involving homologous chromosome set
- P AA (2n)
-
(Duplicate) - F1 AAAA (4n)
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8- Involving non-homologous sets
- P AA (2n) BB (2n)
- G A B
- F1 AB (sterile)
- doubling of chromosome number
- AABB (fertile)
- 2) Fusion of two diploid gametes
- P AA (2n) AA (2n)
- G AA AA
- FI AAAA
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9Polyploidy
- Autopolyploidy
- Is an individual that has more than two
chromosome sets, all derived from a single
species - The chromosomes set are homologous with the
parent cell - Involve homologous chromosome
- Importance in economic value which autopolyploid
plants produce flowers and fruits bigger than
normal diploid plants
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101 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
11- Allopolyploidy
- A polyploid resulting from 2 different species
(hybridization) interbreeding and combining their
chromosomes - The chromosome sets are different to parental
cell - Homologous chromosome sets not involve
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12- F1 hybrids produced from different species are
usually sterile (haploid set of chromosome from
one species cannot pair during meiosis with the
haploid set from the other species) - Chromosome number in a sterile hybrid becomes
doubled and produces fertile hybrids (synapsis
and segregation can occur and viable gametes can
be produced) - Importance in producing new species
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13Spartina alternifora BB (2n70)
Spartina maritina AA (2n56)
x
n35
n28
Sterile hibrid
AB
n63
duplication
Spartina townsendii (fertile) AABB 2n126
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141 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
15Primula floribunda AA (2n 18 ) n9
Primula verticillata BB (2n 18 ) n9
X
Primula kewensis Sterile hybrid AB (n 18)
Doubling of chromosome number
Primula kewensis fertile AABB
(2n 36)
tetraploid
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161 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
17X
Triticum monococcum (Einkorn wheat) AA (2n 14
)
Triticum searsii (Wild grass) BB (2n 14 )
Sterile hybrid AB
X
Triticum turgidum (Emmer wheat) AA BB (2n 28 )
Triticum tauschii (Wild grass) CC (2n 14 )
Sterile hybrid ABC
Triticum aestivum AA BB CC (2n 42)
Hexaploid of original einkorn wheat
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181 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
191 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19