All human being start off with one cell, or a zygote, that is the
product of the union of two other cells, a sperm cell from the father and an
egg cell from the mother. That one cell contains every single genetic
instruction to manufacture the proteins used to build a human being. Our
genes are organized by twenty- three pairs of chromosomes, so forty- six in total.
One set of the chromosomes come from the father and one comes from the mother.
They carry instructions for our bodies to carry out tasks. Also, many advances
are happening. Scientists now think that "junk DNA" is not useless.
Also, evolution is not random because there are cells that
proofread the process of copying genes, and errors rarely
happen. Nobel-prize winning scientist, Barbara McClintock found that corn
genes mutated faster when the corn was under stress like drought or extreme
heat and this is called “jumping genes”, which is when the cell suppresses the
proofreading cells so mutation will occur. Viruses also contribute to evolution
because jumping genes occur in viruses which is called retrotransposons,
there is also another kind of jumping genes called DNA transposons.
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