As you move down a group, atomic radius increases
A person with this genetic disorder has an extra x-chromosome. Their genotype is XXY.
Myelin sheath. It is a layer of lipids produced by Schwaan cells around the axon of neurons. The sheath increased the rate of electric impulse transmission through the axon, several folds. This process is called saltatory conduction where impulse ostensibly hops from a node to another.
The answer to this question in the phase Interphase when the chromosomes replicate to form joined sister chromatids , and also the dna gets replicated
