The chromosomal mutation in the zygote can be traced back to "Chromosome 6 in the egg cell".
<u>Option: B</u>
<u>Explanation:</u>
In germ cells i.e. egg or sperm cells, the mutations in chromosome often happen during the meiosis phase. The number of chromosomes in egg cells or sperm cells must be haploid, so that diploid chromosomes form zygote on fertilization. Chromosome mutation in meiosis leads in an additional set of chromosomes or structural defects in the chromosome.
Chromosomal mutations are often caused by chemical agents or by mutagens.
The homologous chromosomes are segregated from sister chromatids throughout cell division, any abnormality at this point allows the chromosomes to be unequally divided or not disjuncted, same is observed in the situation seen in egg cell chromosome 6.
The basic structure of a muscle fiber is comprised of actin and myosin protein chains that straddle each other in a fusiform arrangement. The actin and myosin arrays interlock and move past each other to cause contraction of the muscle. They then move back to their initial positions in relaxation. This gives muscles their elasticity and distensibility. The muscle fibers are bundled, in their 10s to 100s up into myofibrils around an endomysium. Many myofibrils are also bound up in a perimysium to form a muscle fiber.
Because of their biological point of view which showing their structural resemblance (morphological resemblance) and can interbreed under natural conditions(favour condition) which allow them to produce fertile offspring freely.that's why Asian and African elephants have capable to survive.