Answer:
Tetraploid wheat evolved by allopolyploidization and subsequent diploid-like behavior due to cytological diploidization
Explanation:
Durum wheat (<em>Triticum durum</em>) or pasta wheat, is a tetraploid wheat species that has 28 chromosomes, i.e., seven pairs in each genome (2n = 4x = 28). Durum wheat was domesticated from wild emmer wheat, which originated by hybridization of two diploid wheat species with 14 chromosomes: <em>Triticum monococcum</em> (genome AA) and one wild progenitor (genome BB). <em>Triticum durum </em>is a typical example of evolution by hybridization and polyploidization, where the resultant tetraploid species has two complete sets of chromosomes. Allopolyploidization is one of the most common types of plant speciation. During meiosis, 28 chromosomes form 14 homologous chromosome pairs, because homologous chromosomes have developed 'restriction of pairing' (i.e., cytological diploidization). The restriction of pairing to fully homologous chromosomes ensures a correct meiotic behavior, which otherwise would be altered due to the high level of homology that still exists among chromosomes from different wheat progenitors.
i pretty sure its Cytokinesis and Spindle Fibers.
The answer is b because diffusion is the transfer of particals from high to low and osmosis involves water
Answer:
<u>Sister chromatids are identical forms of chromatids of a chromosomes. They are mostly formed by semi-conservative replication of DNA molecule of a single chromosome.Thus they are like </u><u>'photocopies' </u><u> of original parent chromosomes; joined together at the Centromere</u>.
They are exactly similar in all ramification; with the same gene and allele compositions..
<u>However; slight differences arise between the two identical sisters due to </u><u>mutation</u><u> from</u><u> errors </u><u>at replication;and also in the length of telomere repeats.</u>
Non-sister chromatids are dissimilar forms of chromatids of a chromosomes formed when each half of a chromosome at fertilisation from separate haploid sex-cells, of each parent. fused.They contain different genetic composition;because they are not on the same homologous chromosomes.Therefore crossing -over ensure variation.
<u>However, they are genetically similar in composition; if they are contained in homologous chromosomes</u>. This is because Synapsis of bivalent of these chromosomes allow genetic material to be shared by chromosomal crossing-over between the non-sister chromatids on the chromosomes ; therefore identical genetic characteristics are shared .
Explanation:
