If two parents are contributing genetic material to their offspring, why don’t the genes and chromosomes double in each generation?

Natalie had random hand movements when she was two months old. when she was six months old, she used to grab a block with her whole hand. now at the age of ten months, she can grasp the same block with her thumb and forefinger. this sequence of growth in her hand and finger movements is according to the pattern.

Which of these parts of the membrane large moecules pass through it ?

What material did the moon come from?