Explain the consistency of Mendelian’s law with the chromosome theory of inheritance. Draw the figures of each law.
The chromosome theories of inheritance are based on a few fundamental principles.
1. Chromosome contains genetics materials that is transmitted from parent to offspring and from cell to cell.
2. Chromosomes are replicated and pass along, generation after generation, from parent to offspring. They are also passing from cell to cell during the cellular development of an organism. Each times of chromosome retains its individuality during cell division and gamete formation.
3. The nuclei of most eukaryotic have chromosomes that are that are found in homologous pair.
4. During the formation of haploid cell, different types of (no homologous) chromosome segregate independently to each other.
5. Each parent contributes one set of chromosome to its offspring. The maternal and paternal sets of chromosome are functionally equivalent.
The figures (A) next show the law of segregation. From here we can see the movement of chromosome. A heterozygous individual would only pass one of these two allele to each offspring. In other words, a gamete may contain only single allele not both allele. This is because homologous chromosome segregate from each other, a gamete will contain only one copy of each type of chromosome.
The figures(B) next show considered the segregation of two type of chromosome, each carrying a different gene. At metaphase of meiosis I, the different types of chromosome have randomly aligned along the metaphase plate. This also can occur in one way. The random alignment of chromatid pairs during meiosis I can lead to an independent assortment of genes that are found on non homologous chromosomes.
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